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[PATCH 1/9] rewrite infinite loop in our style
356+ messages / 2 participants
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* [PATCH 1/9] rewrite infinite loop in our style
@ 2026-03-11 14:36 Álvaro Herrera <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Álvaro Herrera @ 2026-03-11 14:36 UTC (permalink / raw)

---
 src/backend/commands/cluster.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c
index 8b5571374d0..da4919e497a 100644
--- a/src/backend/commands/cluster.c
+++ b/src/backend/commands/cluster.c
@@ -4062,8 +4062,14 @@ repack_worker_internal(dsm_segment *seg)
 	 */
 	InvalidateCatalogSnapshot();
 
-	while (!decode_concurrent_changes(decoding_ctx, shared))
-		;
+	for (;;)
+	{
+		bool	stop = decode_concurrent_changes(decoding_ctx, shared);
+
+		if (stop)
+			break;
+
+	}
 
 	/* Cleanup. */
 	cleanup_logical_decoding(decoding_ctx);
-- 
2.47.3


--pnppmxqkefjd4hu2
Content-Type: text/plain; charset=utf-8
Content-Disposition: attachment;
	filename*0="0002-rename-setup_logical_decoding-to-repack_setup_logica.noc";
	filename*1="fbot.txt"



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index c0640e071b9..17fcd246b0c 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Xf36GNcW+0xZNily
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v2-0004-use-Buffer-instead-of-buffer-ID-for-startup-s-buf.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 356+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 356+ messages in thread


end of thread, other threads:[~2026-07-09 18:57 UTC | newest]

Thread overview: 356+ messages (download: mbox mbox.gz follow: Atom feed)
-- links below jump to the message on this page --
2026-03-11 14:36 [PATCH 1/9] rewrite infinite loop in our style Álvaro Herrera <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v2 3/9] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>

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