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[PATCH v2 2/6] Handle pg_get_viewdef default args in system_functions.sql
346+ messages / 2 participants
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* [PATCH v2 2/6] Handle pg_get_viewdef default args in system_functions.sql
@ 2025-12-09 17:33  Mark Wong <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Mark Wong @ 2025-12-09 17:33 UTC (permalink / raw)

Modernize pg_get_viewdef to use CREATE OR REPLACE FUNCTION to handle the
optional pretty argument for both versions that use OID or view name.
---
 src/backend/catalog/system_functions.sql | 14 ++++++++
 src/backend/utils/adt/ruleutils.c        | 44 ------------------------
 src/include/catalog/pg_proc.dat          | 11 ++----
 3 files changed, 16 insertions(+), 53 deletions(-)

diff --git a/src/backend/catalog/system_functions.sql b/src/backend/catalog/system_functions.sql
index 3aad2fbf8f3..4ddbf194fa8 100644
--- a/src/backend/catalog/system_functions.sql
+++ b/src/backend/catalog/system_functions.sql
@@ -664,6 +664,20 @@ LANGUAGE INTERNAL
 PARALLEL SAFE
 AS 'pg_get_ruledef';
 
+CREATE OR REPLACE FUNCTION
+  pg_get_viewdef(view text, pretty bool DEFAULT false)
+RETURNS TEXT
+LANGUAGE INTERNAL
+PARALLEL RESTRICTED
+AS 'pg_get_viewdef_name';
+
+CREATE OR REPLACE FUNCTION
+  pg_get_viewdef(view oid, pretty bool DEFAULT false)
+RETURNS TEXT
+LANGUAGE INTERNAL
+PARALLEL RESTRICTED
+AS 'pg_get_viewdef';
+
 --
 -- The default permissions for functions mean that anyone can execute them.
 -- A number of functions shouldn't be executable by just anyone, but rather
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index c4d424ba10d..57b4adc0e2a 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -658,25 +658,6 @@ pg_get_ruledef_worker(Oid ruleoid, int prettyFlags)
  */
 Datum
 pg_get_viewdef(PG_FUNCTION_ARGS)
-{
-	/* By OID */
-	Oid			viewoid = PG_GETARG_OID(0);
-	int			prettyFlags;
-	char	   *res;
-
-	prettyFlags = PRETTYFLAG_INDENT;
-
-	res = pg_get_viewdef_worker(viewoid, prettyFlags, WRAP_COLUMN_DEFAULT);
-
-	if (res == NULL)
-		PG_RETURN_NULL();
-
-	PG_RETURN_TEXT_P(string_to_text(res));
-}
-
-
-Datum
-pg_get_viewdef_ext(PG_FUNCTION_ARGS)
 {
 	/* By OID */
 	Oid			viewoid = PG_GETARG_OID(0);
@@ -716,31 +697,6 @@ pg_get_viewdef_wrap(PG_FUNCTION_ARGS)
 
 Datum
 pg_get_viewdef_name(PG_FUNCTION_ARGS)
-{
-	/* By qualified name */
-	text	   *viewname = PG_GETARG_TEXT_PP(0);
-	int			prettyFlags;
-	RangeVar   *viewrel;
-	Oid			viewoid;
-	char	   *res;
-
-	prettyFlags = PRETTYFLAG_INDENT;
-
-	/* Look up view name.  Can't lock it - we might not have privileges. */
-	viewrel = makeRangeVarFromNameList(textToQualifiedNameList(viewname));
-	viewoid = RangeVarGetRelid(viewrel, NoLock, false);
-
-	res = pg_get_viewdef_worker(viewoid, prettyFlags, WRAP_COLUMN_DEFAULT);
-
-	if (res == NULL)
-		PG_RETURN_NULL();
-
-	PG_RETURN_TEXT_P(string_to_text(res));
-}
-
-
-Datum
-pg_get_viewdef_name_ext(PG_FUNCTION_ARGS)
 {
 	/* By qualified name */
 	text	   *viewname = PG_GETARG_TEXT_PP(0);
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 597c468983e..9b87b9eda5f 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -3961,13 +3961,6 @@
   proargtypes => 'oid oid', prosrc => 'oidge' },
 
 # System-view support functions
-{ oid => '1640', descr => 'select statement of a view',
-  proname => 'pg_get_viewdef', provolatile => 's', proparallel => 'r',
-  prorettype => 'text', proargtypes => 'text',
-  prosrc => 'pg_get_viewdef_name' },
-{ oid => '1641', descr => 'select statement of a view',
-  proname => 'pg_get_viewdef', provolatile => 's', proparallel => 'r',
-  prorettype => 'text', proargtypes => 'oid', prosrc => 'pg_get_viewdef' },
 { oid => '1642', descr => 'role name by OID (with fallback)',
   proname => 'pg_get_userbyid', provolatile => 's', prorettype => 'name',
   proargtypes => 'oid', prosrc => 'pg_get_userbyid' },
@@ -8510,12 +8503,12 @@
   descr => 'select statement of a view with pretty-print option',
   proname => 'pg_get_viewdef', provolatile => 's', proparallel => 'r',
   prorettype => 'text', proargtypes => 'text bool',
-  prosrc => 'pg_get_viewdef_name_ext' },
+  prosrc => 'pg_get_viewdef_name' },
 { oid => '2506',
   descr => 'select statement of a view with pretty-print option',
   proname => 'pg_get_viewdef', provolatile => 's', proparallel => 'r',
   prorettype => 'text', proargtypes => 'oid bool',
-  prosrc => 'pg_get_viewdef_ext' },
+  prosrc => 'pg_get_viewdef' },
 { oid => '3159',
   descr => 'select statement of a view with pretty-printing and specified line wrapping',
   proname => 'pg_get_viewdef', provolatile => 's', proparallel => 'r',
-- 
2.43.0


--3/nz5wg6+DYwHsLU
Content-Type: text/x-diff; charset=us-ascii
Content-Disposition: attachment;
	filename="v2-0003-Handle-pg_get_indexdef-default-args-in-system_fun.patch"



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

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

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

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

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

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

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

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

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

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

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

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

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

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

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

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

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

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

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

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

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

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

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


--Ot5x3ffkWEuxilWO
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Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


--Ot5x3ffkWEuxilWO
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Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


--Ot5x3ffkWEuxilWO
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Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


--Ot5x3ffkWEuxilWO
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Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


--Ot5x3ffkWEuxilWO
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Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


--Ot5x3ffkWEuxilWO
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Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


--Ot5x3ffkWEuxilWO
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Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
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Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57  Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c
index 89e9d224eec..57f5f26bbec 100644
--- a/src/backend/access/transam/parallel.c
+++ b/src/backend/access/transam/parallel.c
@@ -37,7 +37,6 @@
 #include "storage/ipc.h"
 #include "storage/predicate.h"
 #include "storage/proc.h"
-#include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/combocid.h"
 #include "utils/guc.h"
@@ -101,11 +100,8 @@ typedef struct FixedParallelState
 	TimestampTz stmt_ts;
 	SerializableXactHandle serializable_xact_handle;
 
-	/* Mutex protects remaining fields. */
-	slock_t		mutex;
-
 	/* Maximum XactLastRecEnd of any worker. */
-	XLogRecPtr	last_xlog_end;
+	pg_atomic_uint64 last_xlog_end;
 } FixedParallelState;
 
 /*
@@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt)
 	fps->xact_ts = GetCurrentTransactionStartTimestamp();
 	fps->stmt_ts = GetCurrentStatementStartTimestamp();
 	fps->serializable_xact_handle = ShareSerializableXact();
-	SpinLockInit(&fps->mutex);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 	shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps);
 
 	/* We can skip the rest of this if we're not budgeting for any workers. */
@@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt)
 
 	/* Reset a few bits of fixed parallel state to a clean state. */
 	fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-	fps->last_xlog_end = InvalidXLogRecPtr;
+	pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr);
 
 	/* Recreate error queues (if they exist). */
 	if (pcxt->nworkers > 0)
@@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt)
 	if (pcxt->toc != NULL)
 	{
 		FixedParallelState *fps;
+		XLogRecPtr	last_xlog_end;
 
 		fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false);
-		if (fps->last_xlog_end > XactLastRecEnd)
-			XactLastRecEnd = fps->last_xlog_end;
+		last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end);
+		if (last_xlog_end > XactLastRecEnd)
+			XactLastRecEnd = last_xlog_end;
 	}
 }
 
@@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end)
 	FixedParallelState *fps = MyFixedParallelState;
 
 	Assert(fps != NULL);
-	SpinLockAcquire(&fps->mutex);
-	if (fps->last_xlog_end < last_xlog_end)
-		fps->last_xlog_end = last_xlog_end;
-	SpinLockRelease(&fps->mutex);
+	pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end);
 }
 
 /*
-- 
2.50.1 (Apple Git-155)


--Ot5x3ffkWEuxilWO
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment;
	filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch



^ permalink  raw  reply  [nested|flat] 346+ 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; 346+ messages in thread

From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw)

---
 src/backend/access/transam/parallel.c | 22 ++++++++--------------
 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] 346+ messages in thread


end of thread, other threads:[~2026-07-09 18:57 UTC | newest]

Thread overview: 346+ messages (download: mbox mbox.gz follow: Atom feed)
-- links below jump to the message on this page --
2025-12-09 17:33 [PATCH v2 2/6] Handle pg_get_viewdef default args in system_functions.sql Mark Wong <[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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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]>

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