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Re: [PATCH] PostgreSQL 9.4 mmap(2) performance regression on FreeBSD...
498+ messages / 3 participants
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* Re: [PATCH] PostgreSQL 9.4 mmap(2) performance regression on FreeBSD...
@ 2015-03-19 16:16  Bruce Momjian <[email protected]>
  0 siblings, 2 replies; 498+ messages in thread

From: Bruce Momjian @ 2015-03-19 16:16 UTC (permalink / raw)
  To: Andres Freund <[email protected]>; +Cc: Robert Haas <[email protected]>; Sean Chittenden <[email protected]>; pgsql-hackers

On Mon, Oct 13, 2014 at 11:35:18AM -0400, Bruce Momjian wrote:
> On Mon, Oct 13, 2014 at 05:21:32PM +0200, Andres Freund wrote:
> > > If we have it, we should improve it, or remove it.  We might want to use
> > > this code for something else in the future, so it should be improved
> > > where feasible.
> > 
> > Meh. We don't put in effort into code that doesn't matter just because
> > it might get used elsewhere some day. By that argument we'd need to
> > performance optimize a lot of code. And actually, using that code
> > somewhere else is more of a counter indication than a pro
> > argument. MAP_NOSYNC isn't a general purpose flag.
> 
> The key is that this is platform-specific behavior, so if we should use
> a flag to use it right, we should.  You are right that optimizing
> rarely used code with generic calls isn't a good use of time.

I have adjusted Sean's mmap() options patch to match our C layout and
plan to apply this to head, as it is from August.

-- 
  Bruce Momjian  <[email protected]>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + Everyone has their own god. +


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Attachments:

  [text/x-diff] mmap.diff (1.7K, ../../[email protected]/2-mmap.diff)
  download | inline diff:
diff --git a/src/backend/storage/ipc/dsm_impl.c b/src/backend/storage/ipc/dsm_impl.c
new file mode 100644
index cf7938c..0859fbf
*** a/src/backend/storage/ipc/dsm_impl.c
--- b/src/backend/storage/ipc/dsm_impl.c
*************** dsm_impl_posix(dsm_op op, dsm_handle han
*** 368,374 ****
  
  	/* Map it. */
  	address = mmap(NULL, request_size, PROT_READ | PROT_WRITE,
! 				   MAP_SHARED | MAP_HASSEMAPHORE, fd, 0);
  	if (address == MAP_FAILED)
  	{
  		int			save_errno;
--- 368,374 ----
  
  	/* Map it. */
  	address = mmap(NULL, request_size, PROT_READ | PROT_WRITE,
! 				   MAP_SHARED | MAP_HASSEMAPHORE | MAP_NOSYNC, fd, 0);
  	if (address == MAP_FAILED)
  	{
  		int			save_errno;
*************** dsm_impl_mmap(dsm_op op, dsm_handle hand
*** 960,966 ****
  
  	/* Map it. */
  	address = mmap(NULL, request_size, PROT_READ | PROT_WRITE,
! 				   MAP_SHARED | MAP_HASSEMAPHORE, fd, 0);
  	if (address == MAP_FAILED)
  	{
  		int			save_errno;
--- 960,966 ----
  
  	/* Map it. */
  	address = mmap(NULL, request_size, PROT_READ | PROT_WRITE,
! 				   MAP_SHARED | MAP_HASSEMAPHORE | MAP_NOSYNC, fd, 0);
  	if (address == MAP_FAILED)
  	{
  		int			save_errno;
diff --git a/src/include/portability/mem.h b/src/include/portability/mem.h
new file mode 100644
index 7c77dbd..a4b01fe
*** a/src/include/portability/mem.h
--- b/src/include/portability/mem.h
***************
*** 30,35 ****
--- 30,43 ----
  #define MAP_HASSEMAPHORE		0
  #endif
  
+ /*
+  * BSD-derived systems use the MAP_NOSYNC flag to prevent dirty mmap(2)
+  * pages from being gratuitously flushed to disk.
+  */
+ #ifndef MAP_NOSYNC
+ #define MAP_NOSYNC			0
+ #endif
+ 
  #define PG_MMAP_FLAGS			(MAP_SHARED|MAP_ANONYMOUS|MAP_HASSEMAPHORE)
  
  /* Some really old systems don't define MAP_FAILED. */


^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* Re: [PATCH] PostgreSQL 9.4 mmap(2) performance regression on FreeBSD...
@ 2015-03-19 18:06  Robert Haas <[email protected]>
  parent: Bruce Momjian <[email protected]>
  1 sibling, 0 replies; 498+ messages in thread

From: Robert Haas @ 2015-03-19 18:06 UTC (permalink / raw)
  To: Bruce Momjian <[email protected]>; +Cc: Andres Freund <[email protected]>; Sean Chittenden <[email protected]>; pgsql-hackers

On Thu, Mar 19, 2015 at 12:16 PM, Bruce Momjian <[email protected]> wrote:
> On Mon, Oct 13, 2014 at 11:35:18AM -0400, Bruce Momjian wrote:
>> On Mon, Oct 13, 2014 at 05:21:32PM +0200, Andres Freund wrote:
>> > > If we have it, we should improve it, or remove it.  We might want to use
>> > > this code for something else in the future, so it should be improved
>> > > where feasible.
>> >
>> > Meh. We don't put in effort into code that doesn't matter just because
>> > it might get used elsewhere some day. By that argument we'd need to
>> > performance optimize a lot of code. And actually, using that code
>> > somewhere else is more of a counter indication than a pro
>> > argument. MAP_NOSYNC isn't a general purpose flag.
>>
>> The key is that this is platform-specific behavior, so if we should use
>> a flag to use it right, we should.  You are right that optimizing
>> rarely used code with generic calls isn't a good use of time.
>
> I have adjusted Sean's mmap() options patch to match our C layout and
> plan to apply this to head, as it is from August.

Looks great, thanks for taking care of that.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company


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^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* Re: [PATCH] PostgreSQL 9.4 mmap(2) performance regression on FreeBSD...
@ 2015-03-22 02:06  Bruce Momjian <[email protected]>
  parent: Bruce Momjian <[email protected]>
  1 sibling, 0 replies; 498+ messages in thread

From: Bruce Momjian @ 2015-03-22 02:06 UTC (permalink / raw)
  To: Andres Freund <[email protected]>; +Cc: Robert Haas <[email protected]>; Sean Chittenden <[email protected]>; pgsql-hackers

On Thu, Mar 19, 2015 at 12:16:07PM -0400, Bruce Momjian wrote:
> On Mon, Oct 13, 2014 at 11:35:18AM -0400, Bruce Momjian wrote:
> > On Mon, Oct 13, 2014 at 05:21:32PM +0200, Andres Freund wrote:
> > > > If we have it, we should improve it, or remove it.  We might want to use
> > > > this code for something else in the future, so it should be improved
> > > > where feasible.
> > > 
> > > Meh. We don't put in effort into code that doesn't matter just because
> > > it might get used elsewhere some day. By that argument we'd need to
> > > performance optimize a lot of code. And actually, using that code
> > > somewhere else is more of a counter indication than a pro
> > > argument. MAP_NOSYNC isn't a general purpose flag.
> > 
> > The key is that this is platform-specific behavior, so if we should use
> > a flag to use it right, we should.  You are right that optimizing
> > rarely used code with generic calls isn't a good use of time.
> 
> I have adjusted Sean's mmap() options patch to match our C layout and
> plan to apply this to head, as it is from August.

Patch applied.

-- 
  Bruce Momjian  <[email protected]>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + Everyone has their own god. +


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^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--





^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread

* [PATCH] Restructure repack worker teardown
@ 2026-05-18 17:13  Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 498+ messages in thread

From: Álvaro Herrera @ 2026-05-18 17:13 UTC (permalink / raw)

The original code would leave a shared memory segment unreleased if we
fail partway through initialization.  Change the shutdown order so that
we already free it.

Author: Álvaro Herrera <[email protected]>
Discussion: https://postgr.es/m/[email protected]
---
 src/backend/commands/repack.c | 67 ++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/src/backend/commands/repack.c b/src/backend/commands/repack.c
index bfc62c8f752..c9064d8fd13 100644
--- a/src/backend/commands/repack.c
+++ b/src/backend/commands/repack.c
@@ -3411,10 +3411,14 @@ start_repack_decoding_worker(Oid relid)
 	shm_mq_handle *mqh;
 	BackgroundWorker bgw;
 
+	decoding_worker = palloc0_object(DecodingWorker);
+
 	/* Setup shared memory. */
 	size = BUFFERALIGN(offsetof(DecodingWorkerShared, error_queue)) +
 		BUFFERALIGN(REPACK_ERROR_QUEUE_SIZE);
 	seg = dsm_create(size, 0);
+	decoding_worker->seg = seg;
+
 	shared = (DecodingWorkerShared *) dsm_segment_address(seg);
 	shared->initialized = false;
 	shared->lsn_upto = InvalidXLogRecPtr;
@@ -3454,14 +3458,12 @@ start_repack_decoding_worker(Oid relid)
 	bgw.bgw_main_arg = UInt32GetDatum(dsm_segment_handle(seg));
 	bgw.bgw_notify_pid = MyProcPid;
 
-	decoding_worker = palloc0_object(DecodingWorker);
 	if (!RegisterDynamicBackgroundWorker(&bgw, &decoding_worker->handle))
 		ereport(ERROR,
 				errcode(ERRCODE_CONFIGURATION_LIMIT_EXCEEDED),
 				errmsg("out of background worker slots"),
 				errhint("You might need to increase \"%s\".", "max_worker_processes"));
 
-	decoding_worker->seg = seg;
 	decoding_worker->error_mqh = mqh;
 
 	/*
@@ -3487,17 +3489,6 @@ start_repack_decoding_worker(Oid relid)
 	ConditionVariableCancelSleep();
 }
 
-/*
- * PG_ENSURE_ERROR_CLEANUP callback to stop the decoding worker.
- * This ensures the worker is terminated on both ERROR and FATAL exits,
- * unlike PG_FINALLY which only handles ERROR.
- */
-static void
-repack_decoding_worker_cleanup_cb(int code, Datum arg)
-{
-	stop_repack_decoding_worker();
-}
-
 /*
  * Stop the decoding worker and cleanup the related resources.
  *
@@ -3508,39 +3499,43 @@ static void
 stop_repack_decoding_worker(void)
 {
 	BgwHandleStatus status;
+	dsm_segment	   *dsmseg;
 
-	/* Haven't reached the worker startup? */
+	/* Nothing to do if no worker was set up. */
 	if (decoding_worker == NULL)
 		return;
 
-	/* Could not register the worker? */
-	if (decoding_worker->handle == NULL)
-		return;
+	/* Terminate the worker process, if one is running. */
+	if (decoding_worker->handle != NULL)
+	{
+		TerminateBackgroundWorker(decoding_worker->handle);
+		/* The worker should really exit before the REPACK command does. */
+		HOLD_INTERRUPTS();
+		status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
+		RESUME_INTERRUPTS();
 
-	TerminateBackgroundWorker(decoding_worker->handle);
-	/* The worker should really exit before the REPACK command does. */
-	HOLD_INTERRUPTS();
-	status = WaitForBackgroundWorkerShutdown(decoding_worker->handle);
-	RESUME_INTERRUPTS();
-
-	if (status == BGWH_POSTMASTER_DIED)
-		ereport(FATAL,
-				errcode(ERRCODE_ADMIN_SHUTDOWN),
-				errmsg("postmaster exited during REPACK command"));
-
-	shm_mq_detach(decoding_worker->error_mqh);
+		if (status == BGWH_POSTMASTER_DIED)
+			ereport(FATAL,
+					errcode(ERRCODE_ADMIN_SHUTDOWN),
+					errmsg("postmaster exited during REPACK command"));
+	}
 
 	/*
-	 * If we could not cancel the current sleep due to ERROR, do that before
-	 * we detach from the shared memory the condition variable is located in.
-	 * If we did not, the bgworker ERROR handling code would try and fail
-	 * badly.
+	 * Now detach from our shared memory segment.  In error cases there might
+	 * still be messages from the worker in the queue, which ProcessInterrupts
+	 * would try to read; this is pointless (and causes an assertion failure),
+	 * so set the global pointer to NULL to have ProcessRepackMessages ignore
+	 * them.
 	 */
-	ConditionVariableCancelSleep();
-
-	dsm_detach(decoding_worker->seg);
+	dsmseg = decoding_worker->seg;
 	pfree(decoding_worker);
 	decoding_worker = NULL;
+
+	/* We must also cancel the current sleep, if one is still set up */
+	ConditionVariableCancelSleep();
+
+	if (dsmseg != NULL)
+		dsm_detach(dsmseg);
 }
 
 /* stop_repack_decoding_worker, wrapped as a before_shmem_exit callback */
-- 
2.47.3


--b42ct6adeyjj4cbm--






^ permalink  raw  reply  [nested|flat] 498+ messages in thread


end of thread, other threads:[~2026-05-18 17:13 UTC | newest]

Thread overview: 498+ messages (download: mbox mbox.gz follow: Atom feed)
-- links below jump to the message on this page --
2015-03-19 16:16 Re: [PATCH] PostgreSQL 9.4 mmap(2) performance regression on FreeBSD... Bruce Momjian <[email protected]>
2015-03-19 18:06 ` Robert Haas <[email protected]>
2015-03-22 02:06 ` Bruce Momjian <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>
2026-05-18 17:13 [PATCH] Restructure repack worker teardown Álvaro Herrera <[email protected]>

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