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[PATCH v1 2/2] Don't generate EEOP_*_FETCHSOME operations for slots know to be virtual.
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* [PATCH v1 2/2] Don't generate EEOP_*_FETCHSOME operations for slots know to be virtual.
@ 2019-09-26 18:23  Andres Freund <andres@anarazel.de>
  0 siblings, 0 replies; 399+ messages in thread

From: Andres Freund @ 2019-09-26 18:23 UTC (permalink / raw)

That avoids unnecessary work during both interpreted and JIT compiled
expression evaluation.

Author: Soumyadeep Chakraborty, Andres Freund
Discussion: https://postgr.es/m/CAE-ML+9OKSN71+mHtfMD-L24oDp8dGTfaVjDU6U+j+FNAW5kRQ@mail.gmail.com
---
 src/backend/executor/execExpr.c       |  43 ++++++---
 src/backend/executor/execExprInterp.c | 133 +++++++++++++++++++++++++-
 src/backend/jit/llvm/llvmjit_expr.c   |   6 +-
 3 files changed, 160 insertions(+), 22 deletions(-)

diff --git a/src/backend/executor/execExpr.c b/src/backend/executor/execExpr.c
index 39442f8866f..1ff13d1079a 100644
--- a/src/backend/executor/execExpr.c
+++ b/src/backend/executor/execExpr.c
@@ -65,7 +65,7 @@ static void ExecInitFunc(ExprEvalStep *scratch, Expr *node, List *args,
 static void ExecInitExprSlots(ExprState *state, Node *node);
 static void ExecPushExprSlots(ExprState *state, LastAttnumInfo *info);
 static bool get_last_attnums_walker(Node *node, LastAttnumInfo *info);
-static void ExecComputeSlotInfo(ExprState *state, ExprEvalStep *op);
+static bool ExecComputeSlotInfo(ExprState *state, ExprEvalStep *op);
 static void ExecInitWholeRowVar(ExprEvalStep *scratch, Var *variable,
 								ExprState *state);
 static void ExecInitSubscriptingRef(ExprEvalStep *scratch,
@@ -2285,8 +2285,8 @@ ExecPushExprSlots(ExprState *state, LastAttnumInfo *info)
 		scratch.d.fetch.fixed = false;
 		scratch.d.fetch.kind = NULL;
 		scratch.d.fetch.known_desc = NULL;
-		ExecComputeSlotInfo(state, &scratch);
-		ExprEvalPushStep(state, &scratch);
+		if (ExecComputeSlotInfo(state, &scratch))
+			ExprEvalPushStep(state, &scratch);
 	}
 	if (info->last_outer > 0)
 	{
@@ -2295,8 +2295,8 @@ ExecPushExprSlots(ExprState *state, LastAttnumInfo *info)
 		scratch.d.fetch.fixed = false;
 		scratch.d.fetch.kind = NULL;
 		scratch.d.fetch.known_desc = NULL;
-		ExecComputeSlotInfo(state, &scratch);
-		ExprEvalPushStep(state, &scratch);
+		if (ExecComputeSlotInfo(state, &scratch))
+			ExprEvalPushStep(state, &scratch);
 	}
 	if (info->last_scan > 0)
 	{
@@ -2305,8 +2305,8 @@ ExecPushExprSlots(ExprState *state, LastAttnumInfo *info)
 		scratch.d.fetch.fixed = false;
 		scratch.d.fetch.kind = NULL;
 		scratch.d.fetch.known_desc = NULL;
-		ExecComputeSlotInfo(state, &scratch);
-		ExprEvalPushStep(state, &scratch);
+		if (ExecComputeSlotInfo(state, &scratch))
+			ExprEvalPushStep(state, &scratch);
 	}
 }
 
@@ -2364,14 +2364,21 @@ get_last_attnums_walker(Node *node, LastAttnumInfo *info)
  * The goal is to determine whether a slot is 'fixed', that is, every
  * evaluation of the expression will have the same type of slot, with an
  * equivalent descriptor.
+ *
+ * Returns true if the the deforming step is required, false otherwise.
  */
-static void
+static bool
 ExecComputeSlotInfo(ExprState *state, ExprEvalStep *op)
 {
 	PlanState  *parent = state->parent;
 	TupleDesc	desc = NULL;
 	const TupleTableSlotOps *tts_ops = NULL;
 	bool		isfixed = false;
+	ExprEvalOp	opcode = op->opcode;
+
+	Assert(opcode == EEOP_INNER_FETCHSOME ||
+		   opcode == EEOP_OUTER_FETCHSOME ||
+		   opcode == EEOP_SCAN_FETCHSOME);
 
 	if (op->d.fetch.known_desc != NULL)
 	{
@@ -2383,7 +2390,7 @@ ExecComputeSlotInfo(ExprState *state, ExprEvalStep *op)
 	{
 		isfixed = false;
 	}
-	else if (op->opcode == EEOP_INNER_FETCHSOME)
+	else if (opcode == EEOP_INNER_FETCHSOME)
 	{
 		PlanState  *is = innerPlanState(parent);
 
@@ -2402,7 +2409,7 @@ ExecComputeSlotInfo(ExprState *state, ExprEvalStep *op)
 			desc = ExecGetResultType(is);
 		}
 	}
-	else if (op->opcode == EEOP_OUTER_FETCHSOME)
+	else if (opcode == EEOP_OUTER_FETCHSOME)
 	{
 		PlanState  *os = outerPlanState(parent);
 
@@ -2421,7 +2428,7 @@ ExecComputeSlotInfo(ExprState *state, ExprEvalStep *op)
 			desc = ExecGetResultType(os);
 		}
 	}
-	else if (op->opcode == EEOP_SCAN_FETCHSOME)
+	else if (opcode == EEOP_SCAN_FETCHSOME)
 	{
 		desc = parent->scandesc;
 
@@ -2444,6 +2451,12 @@ ExecComputeSlotInfo(ExprState *state, ExprEvalStep *op)
 		op->d.fetch.kind = NULL;
 		op->d.fetch.known_desc = NULL;
 	}
+
+	/* if the slot is known to always virtual we never need to deform */
+	if (op->d.fetch.fixed && op->d.fetch.kind == &TTSOpsVirtual)
+		return false;
+
+	return true;
 }
 
 /*
@@ -3358,16 +3371,16 @@ ExecBuildGroupingEqual(TupleDesc ldesc, TupleDesc rdesc,
 	scratch.d.fetch.fixed = false;
 	scratch.d.fetch.known_desc = ldesc;
 	scratch.d.fetch.kind = lops;
-	ExecComputeSlotInfo(state, &scratch);
-	ExprEvalPushStep(state, &scratch);
+	if (ExecComputeSlotInfo(state, &scratch))
+		ExprEvalPushStep(state, &scratch);
 
 	scratch.opcode = EEOP_OUTER_FETCHSOME;
 	scratch.d.fetch.last_var = maxatt;
 	scratch.d.fetch.fixed = false;
 	scratch.d.fetch.known_desc = rdesc;
 	scratch.d.fetch.kind = rops;
-	ExecComputeSlotInfo(state, &scratch);
-	ExprEvalPushStep(state, &scratch);
+	if (ExecComputeSlotInfo(state, &scratch))
+		ExprEvalPushStep(state, &scratch);
 
 	/*
 	 * Start comparing at the last field (least significant sort key). That's
diff --git a/src/backend/executor/execExprInterp.c b/src/backend/executor/execExprInterp.c
index e876160a0e7..ccea030cd70 100644
--- a/src/backend/executor/execExprInterp.c
+++ b/src/backend/executor/execExprInterp.c
@@ -160,6 +160,12 @@ static Datum ExecJustAssignOuterVar(ExprState *state, ExprContext *econtext, boo
 static Datum ExecJustAssignScanVar(ExprState *state, ExprContext *econtext, bool *isnull);
 static Datum ExecJustApplyFuncToCase(ExprState *state, ExprContext *econtext, bool *isnull);
 static Datum ExecJustConst(ExprState *state, ExprContext *econtext, bool *isnull);
+static Datum ExecJustInnerVarVirt(ExprState *state, ExprContext *econtext, bool *isnull);
+static Datum ExecJustOuterVarVirt(ExprState *state, ExprContext *econtext, bool *isnull);
+static Datum ExecJustScanVarVirt(ExprState *state, ExprContext *econtext, bool *isnull);
+static Datum ExecJustAssignInnerVarVirt(ExprState *state, ExprContext *econtext, bool *isnull);
+static Datum ExecJustAssignOuterVarVirt(ExprState *state, ExprContext *econtext, bool *isnull);
+static Datum ExecJustAssignScanVarVirt(ExprState *state, ExprContext *econtext, bool *isnull);
 
 
 /*
@@ -255,11 +261,45 @@ ExecReadyInterpretedExpr(ExprState *state)
 			return;
 		}
 	}
-	else if (state->steps_len == 2 &&
-			 state->steps[0].opcode == EEOP_CONST)
+	else if (state->steps_len == 2)
 	{
-		state->evalfunc_private = (void *) ExecJustConst;
-		return;
+		ExprEvalOp	step0 = state->steps[0].opcode;
+
+		if (step0 == EEOP_CONST)
+		{
+			state->evalfunc_private = (void *) ExecJustConst;
+			return;
+		}
+		else if (step0 == EEOP_INNER_VAR)
+		{
+			state->evalfunc_private = (void *) ExecJustInnerVarVirt;
+			return;
+		}
+		else if (step0 == EEOP_OUTER_VAR)
+		{
+			state->evalfunc_private = (void *) ExecJustOuterVarVirt;
+			return;
+		}
+		else if (step0 == EEOP_SCAN_VAR)
+		{
+			state->evalfunc_private = (void *) ExecJustScanVarVirt;
+			return;
+		}
+		else if (step0 == EEOP_ASSIGN_INNER_VAR)
+		{
+			state->evalfunc_private = (void *) ExecJustAssignInnerVarVirt;
+			return;
+		}
+		else if (step0 == EEOP_ASSIGN_OUTER_VAR)
+		{
+			state->evalfunc_private = (void *) ExecJustAssignOuterVarVirt;
+			return;
+		}
+		else if (step0 == EEOP_ASSIGN_SCAN_VAR)
+		{
+			state->evalfunc_private = (void *) ExecJustAssignScanVarVirt;
+			return;
+		}
 	}
 
 #if defined(EEO_USE_COMPUTED_GOTO)
@@ -2096,6 +2136,91 @@ ExecJustConst(ExprState *state, ExprContext *econtext, bool *isnull)
 	return op->d.constval.value;
 }
 
+/* implementation of ExecJust(Inner|Outer|Scan)VarVirt */
+static pg_attribute_always_inline Datum
+ExecJustVarVirtImpl(ExprState *state, TupleTableSlot *slot, bool *isnull)
+{
+	ExprEvalStep *op = &state->steps[0];
+	int			attnum = op->d.var.attnum;
+
+	/*
+	 * As it is guaranteed that a virtual slot is used, there never is a need
+	 * to perform tuple deforming (nor would it be possible). Therefore
+	 * execExpr.c has not emitted a EEOP_*_FETCHSOME step. Verify, as much as
+	 * possible, that that determination was accurate.
+	 */
+	Assert(slot->tts_ops == &TTSOpsVirtual);
+	Assert(TTS_FIXED(slot));
+	Assert(attnum >= 0 && attnum < slot->tts_nvalid);
+
+	*isnull = slot->tts_isnull[attnum];
+
+	return slot->tts_values[attnum];
+}
+
+/* Like ExecJustInnerVar, optimized for virtual slots */
+static Datum
+ExecJustInnerVarVirt(ExprState *state, ExprContext *econtext, bool *isnull)
+{
+	return ExecJustVarVirtImpl(state, econtext->ecxt_innertuple, isnull);
+}
+
+/* Like ExecJustOuterVar, optimized for virtual slots */
+static Datum
+ExecJustOuterVarVirt(ExprState *state, ExprContext *econtext, bool *isnull)
+{
+	return ExecJustVarVirtImpl(state, econtext->ecxt_outertuple, isnull);
+}
+
+/* Like ExecJustScanVar, optimized for virtual slots */
+static Datum
+ExecJustScanVarVirt(ExprState *state, ExprContext *econtext, bool *isnull)
+{
+	return ExecJustVarVirtImpl(state, econtext->ecxt_scantuple, isnull);
+}
+
+/* implementation of ExecJustAssign(Inner|Outer|Scan)VarVirt */
+static pg_attribute_always_inline Datum
+ExecJustAssignVarVirtImpl(ExprState *state, TupleTableSlot *inslot, bool *isnull)
+{
+	ExprEvalStep *op = &state->steps[0];
+	int			attnum = op->d.assign_var.attnum;
+	int			resultnum = op->d.assign_var.resultnum;
+	TupleTableSlot *outslot = state->resultslot;
+
+	/* see ExecJustVarVirtImpl for comments */
+
+	Assert(inslot->tts_ops == &TTSOpsVirtual);
+	Assert(TTS_FIXED(inslot));
+	Assert(attnum >= 0 && attnum < inslot->tts_nvalid);
+
+	outslot->tts_values[resultnum] = inslot->tts_values[attnum];
+	outslot->tts_isnull[resultnum] = inslot->tts_isnull[attnum];
+
+	return 0;
+}
+
+/* Like ExecJustAssignInnerVar, optimized for virtual slots */
+static Datum
+ExecJustAssignInnerVarVirt(ExprState *state, ExprContext *econtext, bool *isnull)
+{
+	return ExecJustAssignVarVirtImpl(state, econtext->ecxt_innertuple, isnull);
+}
+
+/* Like ExecJustAssignOuterVar, optimized for virtual slots */
+static Datum
+ExecJustAssignOuterVarVirt(ExprState *state, ExprContext *econtext, bool *isnull)
+{
+	return ExecJustAssignVarVirtImpl(state, econtext->ecxt_outertuple, isnull);
+}
+
+/* Like ExecJustAssignScanVar, optimized for virtual slots */
+static Datum
+ExecJustAssignScanVarVirt(ExprState *state, ExprContext *econtext, bool *isnull)
+{
+	return ExecJustAssignVarVirtImpl(state, econtext->ecxt_scantuple, isnull);
+}
+
 #if defined(EEO_USE_COMPUTED_GOTO)
 /*
  * Comparator used when building address->opcode lookup table for
diff --git a/src/backend/jit/llvm/llvmjit_expr.c b/src/backend/jit/llvm/llvmjit_expr.c
index 30133634c70..d09324637b9 100644
--- a/src/backend/jit/llvm/llvmjit_expr.c
+++ b/src/backend/jit/llvm/llvmjit_expr.c
@@ -287,6 +287,9 @@ llvm_compile_expr(ExprState *state)
 					if (op->d.fetch.fixed)
 						tts_ops = op->d.fetch.kind;
 
+					/* step should not have been generated */
+					Assert(tts_ops != &TTSOpsVirtual);
+
 					if (opcode == EEOP_INNER_FETCHSOME)
 						v_slot = v_innerslot;
 					else if (opcode == EEOP_OUTER_FETCHSOME)
@@ -297,9 +300,6 @@ llvm_compile_expr(ExprState *state)
 					/*
 					 * Check if all required attributes are available, or
 					 * whether deforming is required.
-					 *
-					 * TODO: skip nvalid check if slot is fixed and known to
-					 * be a virtual slot.
 					 */
 					v_nvalid =
 						l_load_struct_gep(b, v_slot,
-- 
2.23.0.162.gf1d4a28250


--qzo23gnb4cdssny7--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread

* [PATCH] Reproduce filtering issue.
@ 2026-03-23 11:50  Antonin Houska <ah@cybertec.at>
  0 siblings, 0 replies; 399+ messages in thread

From: Antonin Houska @ 2026-03-23 11:50 UTC (permalink / raw)

---
 contrib/test_decoding/expected/filtering.out |  74 ++++++++++++++
 contrib/test_decoding/specs/filtering.spec   | 101 +++++++++++++++++++
 src/backend/executor/nodeModifyTable.c       |   2 +
 src/backend/replication/logical/snapbuild.c  |   3 +
 src/test/isolation/isolationtester.c         |   9 +-
 5 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 contrib/test_decoding/expected/filtering.out
 create mode 100644 contrib/test_decoding/specs/filtering.spec

diff --git a/contrib/test_decoding/expected/filtering.out b/contrib/test_decoding/expected/filtering.out
new file mode 100644
index 00000000000..6ba9690509f
--- /dev/null
+++ b/contrib/test_decoding/expected/filtering.out
@@ -0,0 +1,74 @@
+Parsed test spec with 5 sessions
+
+starting permutation: s1_assign_xid s3_repack s2_assign_xid s1_rollback s4_insert s5_wakeup_snapbuild s2_rollback s5_wakeup_insert_speculative s4_insert_commit s5_wakeup_repack
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+injection_points_attach
+-----------------------
+                       
+(1 row)
+
+step s1_assign_xid: 
+    BEGIN;
+    CREATE TABLE c(i int);
+
+step s3_repack: 
+	REPACK (CONCURRENTLY) a;
+ <waiting ...>
+step s2_assign_xid: 
+    BEGIN;
+    CREATE TABLE d(i int);
+
+step s1_rollback: 
+    ROLLBACK;
+
+step s4_insert: 
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+ <waiting ...>
+step s5_wakeup_snapbuild: 
+	SELECT injection_points_wakeup('snapbuild-full');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s2_rollback: 
+    ROLLBACK;
+
+step s5_wakeup_insert_speculative: 
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s4_insert: <... completed>
+step s4_insert_commit: 
+	COMMIT;
+
+step s5_wakeup_repack: 
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+
+injection_points_wakeup
+-----------------------
+                       
+(1 row)
+
+step s3_repack: <... completed>
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
+injection_points_detach
+-----------------------
+                       
+(1 row)
+
diff --git a/contrib/test_decoding/specs/filtering.spec b/contrib/test_decoding/specs/filtering.spec
new file mode 100644
index 00000000000..a02c9f8facb
--- /dev/null
+++ b/contrib/test_decoding/specs/filtering.spec
@@ -0,0 +1,101 @@
+setup
+{
+	CREATE TABLE a(i int primary key, j int) WITH (autovacuum_enabled = off);
+	INSERT INTO a(i, j) VALUES (1, 1), (2, 2);
+	CREATE TABLE t(i int primary key);
+	INSERT INTO t(i) VALUES (1);
+	CREATE EXTENSION injection_points;
+}
+
+session s1
+step s1_assign_xid
+{
+    BEGIN;
+    CREATE TABLE c(i int);
+}
+step s1_rollback
+{
+    ROLLBACK;
+}
+
+session s2
+step s2_assign_xid
+{
+    BEGIN;
+    CREATE TABLE d(i int);
+}
+step s2_rollback
+{
+    ROLLBACK;
+}
+
+session s3
+setup
+{
+	SELECT injection_points_attach('snapbuild-full', 'wait');
+	SELECT injection_points_attach('repack-concurrently-before-lock', 'wait');
+}
+step s3_repack
+{
+	REPACK (CONCURRENTLY) a;
+}
+teardown
+{
+	SELECT injection_points_detach('repack-concurrently-before-lock');
+	SELECT injection_points_detach('snapbuild-full');
+}
+
+session s4
+setup
+{
+	SELECT injection_points_set_local();
+	SELECT injection_points_attach('insert-speculative-before-confirm', 'wait');
+}
+step s4_insert
+{
+	BEGIN;
+	INSERT INTO t(i)
+	SELECT max(i) + 1 FROM t ON CONFLICT (i) DO UPDATE SET i=EXCLUDED.i;
+}
+step s4_insert_commit
+{
+	COMMIT;
+}
+teardown
+{
+	SELECT injection_points_detach('insert-speculative-before-confirm');
+}
+
+session s5
+step s5_wakeup_snapbuild
+{
+	SELECT injection_points_wakeup('snapbuild-full');
+}
+step s5_wakeup_insert_speculative
+{
+	SELECT injection_points_wakeup('insert-speculative-before-confirm');
+}
+step s5_wakeup_repack
+{
+	SELECT injection_points_wakeup('repack-concurrently-before-lock');
+}
+
+permutation
+# Bring the snapshot builder to the FULL_SNAPSHOT state.
+s1_assign_xid
+s3_repack
+s2_assign_xid
+s1_rollback
+# Perform the speculative insert, but no confirmation so far. The snapshot
+# builder should decode it.
+s4_insert
+# Let the snapshout builder achieve CONSISTENT state and finish the setup.
+s5_wakeup_snapbuild
+s2_rollback
+# While REPACK is waiting on repack-concurrently-before-lock, let the insert
+# get confirmed. Relation filtering is now enabled.
+s5_wakeup_insert_speculative
+s4_insert_commit
+# REPACK should now decode the speculative insert and decode the speculative
+# insert (with the confirmation record filtered out).
+s5_wakeup_repack
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 680c29f35d5..6d5482e5746 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1232,6 +1232,8 @@ ExecInsert(ModifyTableContext *context,
 												   slot, arbiterIndexes,
 												   &specConflict);
 
+			INJECTION_POINT("insert-speculative-before-confirm", NULL);
+
 			/* adjust the tuple's state accordingly */
 			table_tuple_complete_speculative(resultRelationDesc, slot,
 											 specToken, !specConflict);
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index fbdd4600a2b..883e5b6e18f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -141,6 +141,7 @@
 #include "storage/procarray.h"
 #include "storage/standby.h"
 #include "utils/builtins.h"
+#include "utils/injection_point.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/snapshot.h"
@@ -1390,6 +1391,8 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->state = SNAPBUILD_FULL_SNAPSHOT;
 		builder->next_phase_at = running->nextXid;
 
+		INJECTION_POINT("snapbuild-full", NULL);
+
 		ereport(LOG,
 				errmsg("logical decoding found initial consistent point at %X/%08X",
 					   LSN_FORMAT_ARGS(lsn)),
diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 440c875b8ac..8f17ee412c9 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -216,15 +216,22 @@ main(int argc, char **argv)
 	 * exactly expect concurrent use of test tables.  However, autovacuum will
 	 * occasionally take AccessExclusiveLock to truncate a table, and we must
 	 * ignore that transient wait.
+	 *
+	 * If the session's backend is blocked, and if its background worker is
+	 * waiting on an injection point, we assume that the injection point is
+	 * the reason for the backend to be blocked. That's what we check in the
+	 * second query of the UNION. XXX Should we use a separate query for that?
 	 */
 	initPQExpBuffer(&wait_query);
 	appendPQExpBufferStr(&wait_query,
+						 "WITH blocking(res) AS ("
 						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked($1, '{");
 	/* The spec syntax requires at least one session; assume that here. */
 	appendPQExpBufferStr(&wait_query, conns[1].backend_pid_str);
 	for (i = 2; i < nconns; i++)
 		appendPQExpBuffer(&wait_query, ",%s", conns[i].backend_pid_str);
-	appendPQExpBufferStr(&wait_query, "}')");
+	appendPQExpBufferStr(&wait_query, "}') UNION "
+						 "SELECT pg_catalog.pg_isolation_test_session_is_blocked(pid, '{}') FROM pg_stat_activity WHERE leader_pid=$1) SELECT bool_or(res) FROM blocking");
 
 	res = PQprepare(conns[0].conn, PREP_WAITING, wait_query.data, 0, NULL);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-- 
2.47.3


--=-=-=--





^ permalink  raw  reply  [nested|flat] 399+ messages in thread