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[PATCH v6 3/7] Row pattern recognition patch (planner).
113+ messages / 2 participants
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* [PATCH v6 3/7] Row pattern recognition patch (planner).
@ 2023-09-12 05:22 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

From: Tatsuo Ishii @ 2023-09-12 05:22 UTC (permalink / raw)

---
 src/backend/optimizer/plan/createplan.c | 23 ++++++++++++++++++-----
 src/backend/optimizer/plan/setrefs.c    | 23 +++++++++++++++++++++++
 src/include/nodes/plannodes.h           | 15 +++++++++++++++
 3 files changed, 56 insertions(+), 5 deletions(-)

diff --git a/src/backend/optimizer/plan/createplan.c b/src/backend/optimizer/plan/createplan.c
index 34ca6d4ac2..469fcd156b 100644
--- a/src/backend/optimizer/plan/createplan.c
+++ b/src/backend/optimizer/plan/createplan.c
@@ -286,9 +286,10 @@ static WindowAgg *make_windowagg(List *tlist, Index winref,
 								 int ordNumCols, AttrNumber *ordColIdx, Oid *ordOperators, Oid *ordCollations,
 								 int frameOptions, Node *startOffset, Node *endOffset,
 								 Oid startInRangeFunc, Oid endInRangeFunc,
-								 Oid inRangeColl, bool inRangeAsc, bool inRangeNullsFirst,
-								 List *runCondition, List *qual, bool topWindow,
-								 Plan *lefttree);
+								 Oid inRangeColl, bool inRangeAsc, bool inRangeNullsFirst, List *runCondition,
+								 RPSkipTo rpSkipTo, List *patternVariable, List *patternRegexp, List *defineClause,
+								 List *defineInitial,
+								 List *qual, bool topWindow, Plan *lefttree);
 static Group *make_group(List *tlist, List *qual, int numGroupCols,
 						 AttrNumber *grpColIdx, Oid *grpOperators, Oid *grpCollations,
 						 Plan *lefttree);
@@ -2698,6 +2699,11 @@ create_windowagg_plan(PlannerInfo *root, WindowAggPath *best_path)
 						  wc->inRangeAsc,
 						  wc->inRangeNullsFirst,
 						  wc->runCondition,
+						  wc->rpSkipTo,
+						  wc->patternVariable,
+						  wc->patternRegexp,
+						  wc->defineClause,
+						  wc->defineInitial,
 						  best_path->qual,
 						  best_path->topwindow,
 						  subplan);
@@ -6601,8 +6607,10 @@ make_windowagg(List *tlist, Index winref,
 			   int ordNumCols, AttrNumber *ordColIdx, Oid *ordOperators, Oid *ordCollations,
 			   int frameOptions, Node *startOffset, Node *endOffset,
 			   Oid startInRangeFunc, Oid endInRangeFunc,
-			   Oid inRangeColl, bool inRangeAsc, bool inRangeNullsFirst,
-			   List *runCondition, List *qual, bool topWindow, Plan *lefttree)
+			   Oid inRangeColl, bool inRangeAsc, bool inRangeNullsFirst, List *runCondition,
+			   RPSkipTo rpSkipTo, List *patternVariable, List *patternRegexp, List *defineClause,
+			   List *defineInitial,
+			   List *qual, bool topWindow, Plan *lefttree)
 {
 	WindowAgg  *node = makeNode(WindowAgg);
 	Plan	   *plan = &node->plan;
@@ -6628,6 +6636,11 @@ make_windowagg(List *tlist, Index winref,
 	node->inRangeAsc = inRangeAsc;
 	node->inRangeNullsFirst = inRangeNullsFirst;
 	node->topWindow = topWindow;
+	node->rpSkipTo = rpSkipTo,
+	node->patternVariable = patternVariable;
+	node->patternRegexp = patternRegexp;
+	node->defineClause = defineClause;
+	node->defineInitial = defineInitial;
 
 	plan->targetlist = tlist;
 	plan->lefttree = lefttree;
diff --git a/src/backend/optimizer/plan/setrefs.c b/src/backend/optimizer/plan/setrefs.c
index 97fa561e4e..2ed00b5d41 100644
--- a/src/backend/optimizer/plan/setrefs.c
+++ b/src/backend/optimizer/plan/setrefs.c
@@ -2456,6 +2456,29 @@ set_upper_references(PlannerInfo *root, Plan *plan, int rtoffset)
 					   NRM_EQUAL,
 					   NUM_EXEC_QUAL(plan));
 
+	/*
+	 *	Modifies an expression tree in each DEFINE clause so that all Var
+	 *	nodes reference outputs of a subplan.
+	 */
+	if (IsA(plan, WindowAgg))
+	{
+		WindowAgg  *wplan = (WindowAgg *) plan;
+
+		foreach(l, wplan->defineClause)
+		{
+			TargetEntry *tle = (TargetEntry *) lfirst(l);
+
+			tle->expr = (Expr *)
+				fix_upper_expr(root,
+							   (Node *) tle->expr,
+							   subplan_itlist,
+							   OUTER_VAR,
+							   rtoffset,
+							   NRM_EQUAL,
+							   NUM_EXEC_QUAL(plan));
+		}
+	}
+
 	pfree(subplan_itlist);
 }
 
diff --git a/src/include/nodes/plannodes.h b/src/include/nodes/plannodes.h
index 1b787fe031..afa27bb45a 100644
--- a/src/include/nodes/plannodes.h
+++ b/src/include/nodes/plannodes.h
@@ -1096,6 +1096,21 @@ typedef struct WindowAgg
 	/* nulls sort first for in_range tests? */
 	bool		inRangeNullsFirst;
 
+	/* Row Pattern Recognition AFTER MACH SKIP clause */
+	RPSkipTo	rpSkipTo;		/* Row Pattern Skip To type */
+
+	/* Row Pattern PATTERN variable name (list of String) */
+	List		*patternVariable;
+
+	/* Row Pattern RPATTERN regular expression quantifier ('+' or ''. list of String) */
+	List		*patternRegexp;
+
+	/* Row Pattern DEFINE clause (list of TargetEntry) */
+	List	   *defineClause;
+
+	/* Row Pattern DEFINE variable initial names (list of String) */
+	List		*defineInitial;
+
 	/*
 	 * false for all apart from the WindowAgg that's closest to the root of
 	 * the plan
-- 
2.25.1


----Next_Part(Tue_Sep_12_15_18_43_2023_359)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v6-0004-Row-pattern-recognition-patch-executor.patch"



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



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* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic
@ 2026-07-09 18:57 Nathan Bossart <[email protected]>
  0 siblings, 0 replies; 113+ messages in thread

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

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

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


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



^ permalink  raw  reply  [nested|flat] 113+ messages in thread

end of thread, other threads:[~2026-07-09 18:57 UTC | newest]

Thread overview: 113+ messages (download: mbox mbox.gz follow: Atom feed)
-- links below jump to the message on this page --
2023-09-12 05:22 [PATCH v6 3/7] Row pattern recognition patch (planner). Tatsuo Ishii <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan 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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