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[PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
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* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Thu_Jan_21_00_28_44_2021_003)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v5-0003-Poc-Keep-page-LSN-updated-while-WAL-skipping.patch"



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  9 ++++++++-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..1e2c11fdd3 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -552,9 +552,16 @@ typedef struct ViewOptions
 		(relation)->rd_smgr->smgr_targblock = (targblock); \
 	} while (0)
 
+/*
+ * RelationIsPermanent
+ *		True if relation is WAL-logged.
+ */
+#define RelationIsWalLogged(relation)									\
+	((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..35acccb29c 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT \
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Mon_Jan_18_15_08_38_2021_069)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c       |  2 +-
 src/backend/optimizer/util/plancat.c       |  3 ++-
 src/include/utils/rel.h                    |  2 +-
 src/include/utils/snapmgr.h                |  2 +-
 src/test/subscription/t/001_rep_changes.pl | 20 +++++++++++++++++++-
 5 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
diff --git a/src/test/subscription/t/001_rep_changes.pl b/src/test/subscription/t/001_rep_changes.pl
index 0680f44a1a..ed9b48e8bc 100644
--- a/src/test/subscription/t/001_rep_changes.pl
+++ b/src/test/subscription/t/001_rep_changes.pl
@@ -3,7 +3,7 @@ use strict;
 use warnings;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 23;
+use Test::More tests => 24;
 
 # Initialize publisher node
 my $node_publisher = get_new_node('publisher');
@@ -358,3 +358,21 @@ is($result, qq(0), 'check replication origin was dropped on subscriber');
 
 $node_subscriber->stop('fast');
 $node_publisher->stop('fast');
+
+#
+# CREATE PUBLICATION while wal_level=mimal should succeed, with a WARNING
+$node_publisher->append_conf(
+	'postgresql.conf', qq(
+wal_level=minimal
+max_wal_senders=0
+));
+$node_publisher->start;
+($result, my $retout, my $reterr) = $node_publisher->psql(
+	'postgres', qq{
+BEGIN;
+CREATE TABLE skip_wal();
+CREATE PUBLICATION tap_pub2 FOR TABLE skip_wal;
+ROLLBACK;
+});
+ok($reterr =~ m/WARNING:  wal_level is insufficient to publish logical changes/,
+   'test CREATE PUBLICATION can be done while wal_leve=minimal');
-- 
2.27.0


----Next_Part(Tue_Jan_19_13_48_31_2021_529)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence
@ 2021-01-18 05:47  Kyotaro Horiguchi <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Kyotaro Horiguchi @ 2021-01-18 05:47 UTC (permalink / raw)

RelationNeedsWAL() may return false for a permanent relation when
wal_level=minimal and the relation is created or truncated in the
current transaction. Directly examine relpersistence instead of using
the function to know relation persistence.
---
 src/backend/catalog/pg_publication.c | 2 +-
 src/backend/optimizer/util/plancat.c | 3 ++-
 src/include/storage/bufmgr.h         | 8 +++++++-
 src/include/utils/rel.h              | 2 +-
 src/include/utils/snapmgr.h          | 2 +-
 5 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/backend/catalog/pg_publication.c b/src/backend/catalog/pg_publication.c
index 5f8e1c64e1..84d2efcfd2 100644
--- a/src/backend/catalog/pg_publication.c
+++ b/src/backend/catalog/pg_publication.c
@@ -67,7 +67,7 @@ check_publication_add_relation(Relation targetrel)
 				 errdetail("System tables cannot be added to publications.")));
 
 	/* UNLOGGED and TEMP relations cannot be part of publication. */
-	if (!RelationNeedsWAL(targetrel))
+	if (targetrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("table \"%s\" cannot be replicated",
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index da322b453e..177e6e336a 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -126,7 +126,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	relation = table_open(relationObjectId, NoLock);
 
 	/* Temporary and unlogged relations are inaccessible during recovery. */
-	if (!RelationNeedsWAL(relation) && RecoveryInProgress())
+	if (relation->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT &&
+		RecoveryInProgress())
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot access temporary or unlogged relations during recovery")));
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index fb00fda6a7..e641174798 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -14,6 +14,7 @@
 #ifndef BUFMGR_H
 #define BUFMGR_H
 
+#include "access/xlog.h"
 #include "storage/block.h"
 #include "storage/buf.h"
 #include "storage/bufpage.h"
@@ -278,12 +279,17 @@ TestForOldSnapshot(Snapshot snapshot, Relation relation, Page page)
 {
 	Assert(relation != NULL);
 
+	/*
+	 * While wal_level=minimal, early pruning can happen without updating page
+	 * LSN. Don't take the fast-return path while wal_level=minimal so that we
+	 * don't miss early pruning.
+	 */
 	if (old_snapshot_threshold >= 0
 		&& (snapshot) != NULL
 		&& ((snapshot)->snapshot_type == SNAPSHOT_MVCC
 			|| (snapshot)->snapshot_type == SNAPSHOT_TOAST)
 		&& !XLogRecPtrIsInvalid((snapshot)->lsn)
-		&& PageGetLSN(page) > (snapshot)->lsn)
+		&& (!XLogIsNeeded() || PageGetLSN(page) > (snapshot)->lsn))
 		TestForOldSnapshot_impl(snapshot, relation);
 }
 
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..f58d65cf28 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -554,7 +554,7 @@ typedef struct ViewOptions
 
 /*
  * RelationNeedsWAL
- *		True if relation needs WAL.
+ *		True if relation needs WAL at the time.
  *
  * Returns false if wal_level = minimal and this relation is created or
  * truncated in the current transaction.  See "Skipping WAL for New
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
index 579be352c5..c21ee3c289 100644
--- a/src/include/utils/snapmgr.h
+++ b/src/include/utils/snapmgr.h
@@ -37,7 +37,7 @@
  */
 #define RelationAllowsEarlyPruning(rel) \
 ( \
-	 RelationNeedsWAL(rel) \
+	 (rel)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT	\
   && !IsCatalogRelation(rel) \
   && !RelationIsAccessibleInLogicalDecoding(rel) \
 )
-- 
2.27.0


----Next_Part(Wed_Jan_20_17_34_44_2021_328)----





^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* Re: Fix slot synchronization with two_phase decoding enabled
@ 2025-04-01 06:09  Amit Kapila <[email protected]>
  0 siblings, 1 reply; 88+ messages in thread

From: Amit Kapila @ 2025-04-01 06:09 UTC (permalink / raw)
  To: Zhijie Hou (Fujitsu) <[email protected]>; +Cc: PostgreSQL Hackers <[email protected]>

On Mon, Mar 31, 2025 at 5:04 PM Zhijie Hou (Fujitsu)
<[email protected]> wrote:
>
> Thanks for the comments, they have been addressed in V2.
>

In the PG17 patch, we only have a check preventing failover and
two_phase in CreateSubscription. Don't we need a similar check for
AlterSubscription?

Apart from the above, I have a few suggestions for changes in docs,
error messages, and comments for both versions. See attached.

-- 
With Regards,
Amit Kapila.

diff --git a/doc/src/sgml/system-views.sgml b/doc/src/sgml/system-views.sgml
index 141c140331d..bff0d143ac5 100644
--- a/doc/src/sgml/system-views.sgml
+++ b/doc/src/sgml/system-views.sgml
@@ -2566,7 +2566,7 @@ SELECT * FROM pg_locks pl LEFT JOIN pg_prepared_xacts ppx
       </para>
       <para>
        The address (<literal>LSN</literal>) from which the decoding of prepared
-       transactions is enabled. Always <literal>NULL</literal> for physical
+       transactions is enabled. <literal>NULL</literal> for physical
        slots.
       </para></entry>
      </row>
diff --git a/src/test/recovery/t/040_standby_failover_slots_sync.pl b/src/test/recovery/t/040_standby_failover_slots_sync.pl
index 67cc6374565..19273a49914 100644
--- a/src/test/recovery/t/040_standby_failover_slots_sync.pl
+++ b/src/test/recovery/t/040_standby_failover_slots_sync.pl
@@ -896,9 +896,9 @@ is($result, 't',
 # Promote the standby1 to primary. Confirm that:
 # a) the slot 'lsub1_slot' and 'snap_test_slot' are retained on the new primary
 # b) logical replication for regress_mysub1 is resumed successfully after failover
-# c) changes from the transaction 'test_twophase_slotsync', which was prepared
-#    on the old primary, can be consumed from the synced slot 'snap_test_slot'
-#    once committed on the new primary.
+# c) changes from the transaction prepared 'test_twophase_slotsync' can be
+#    consumed from the synced slot 'snap_test_slot' once committed on the new
+#    primary.
 # d) changes can be consumed from the synced slot 'snap_test_slot'
 ##################################################
 $primary->wait_for_replay_catchup($standby1);

diff --git a/src/backend/commands/subscriptioncmds.c b/src/backend/commands/subscriptioncmds.c
index 8308ccaad5a..df7ab827f7d 100644
--- a/src/backend/commands/subscriptioncmds.c
+++ b/src/backend/commands/subscriptioncmds.c
@@ -657,7 +657,7 @@ CreateSubscription(ParseState *pstate, CreateSubscriptionStmt *stmt,
 	if (opts.twophase && opts.failover)
 		ereport(ERROR,
 				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-				errmsg("cannot enable failover option when two_phase option is enabled"));
+				errmsg("failover and two_phase are mutually exclusive options"));
 
 	/*
 	 * If built with appropriate switch, whine when regression-testing
diff --git a/src/backend/replication/slot.c b/src/backend/replication/slot.c
index c1bbd16254e..da510f60f9c 100644
--- a/src/backend/replication/slot.c
+++ b/src/backend/replication/slot.c
@@ -357,7 +357,7 @@ ReplicationSlotCreate(const char *name, bool db_specific,
 		if (two_phase)
 			ereport(ERROR,
 					errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-					errmsg("cannot enable failover for a replication slot that enables two-phase decoding"));
+					errmsg("failover and two_phase are mutually exclusive options"));
 	}
 
 	/*
@@ -873,7 +873,7 @@ ReplicationSlotAlter(const char *name, bool failover)
 	if (failover && MyReplicationSlot->data.two_phase)
 		ereport(ERROR,
 				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-				errmsg("cannot enable failover for a replication slot that enables two-phase decoding"));
+				errmsg("cannot enable failover for a two-phase enabled replication slot"));
 
 	if (MyReplicationSlot->data.failover != failover)
 	{


Attachments:

  [text/plain] v2-0001-Head-amit.1.patch.txt (1.6K, ../../CAA4eK1L7uyJAEJGBEXAYehyG_gfvuQLh5FDqDRf+uJaDT=HggA@mail.gmail.com/2-v2-0001-Head-amit.1.patch.txt)
  download | inline diff:
diff --git a/doc/src/sgml/system-views.sgml b/doc/src/sgml/system-views.sgml
index 141c140331d..bff0d143ac5 100644
--- a/doc/src/sgml/system-views.sgml
+++ b/doc/src/sgml/system-views.sgml
@@ -2566,7 +2566,7 @@ SELECT * FROM pg_locks pl LEFT JOIN pg_prepared_xacts ppx
       </para>
       <para>
        The address (<literal>LSN</literal>) from which the decoding of prepared
-       transactions is enabled. Always <literal>NULL</literal> for physical
+       transactions is enabled. <literal>NULL</literal> for physical
        slots.
       </para></entry>
      </row>
diff --git a/src/test/recovery/t/040_standby_failover_slots_sync.pl b/src/test/recovery/t/040_standby_failover_slots_sync.pl
index 67cc6374565..19273a49914 100644
--- a/src/test/recovery/t/040_standby_failover_slots_sync.pl
+++ b/src/test/recovery/t/040_standby_failover_slots_sync.pl
@@ -896,9 +896,9 @@ is($result, 't',
 # Promote the standby1 to primary. Confirm that:
 # a) the slot 'lsub1_slot' and 'snap_test_slot' are retained on the new primary
 # b) logical replication for regress_mysub1 is resumed successfully after failover
-# c) changes from the transaction 'test_twophase_slotsync', which was prepared
-#    on the old primary, can be consumed from the synced slot 'snap_test_slot'
-#    once committed on the new primary.
+# c) changes from the transaction prepared 'test_twophase_slotsync' can be
+#    consumed from the synced slot 'snap_test_slot' once committed on the new
+#    primary.
 # d) changes can be consumed from the synced slot 'snap_test_slot'
 ##################################################
 $primary->wait_for_replay_catchup($standby1);


  [text/plain] v2-0001-PG17-amit.1.patch.txt (1.6K, ../../CAA4eK1L7uyJAEJGBEXAYehyG_gfvuQLh5FDqDRf+uJaDT=HggA@mail.gmail.com/3-v2-0001-PG17-amit.1.patch.txt)
  download | inline diff:
diff --git a/src/backend/commands/subscriptioncmds.c b/src/backend/commands/subscriptioncmds.c
index 8308ccaad5a..df7ab827f7d 100644
--- a/src/backend/commands/subscriptioncmds.c
+++ b/src/backend/commands/subscriptioncmds.c
@@ -657,7 +657,7 @@ CreateSubscription(ParseState *pstate, CreateSubscriptionStmt *stmt,
 	if (opts.twophase && opts.failover)
 		ereport(ERROR,
 				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-				errmsg("cannot enable failover option when two_phase option is enabled"));
+				errmsg("failover and two_phase are mutually exclusive options"));
 
 	/*
 	 * If built with appropriate switch, whine when regression-testing
diff --git a/src/backend/replication/slot.c b/src/backend/replication/slot.c
index c1bbd16254e..da510f60f9c 100644
--- a/src/backend/replication/slot.c
+++ b/src/backend/replication/slot.c
@@ -357,7 +357,7 @@ ReplicationSlotCreate(const char *name, bool db_specific,
 		if (two_phase)
 			ereport(ERROR,
 					errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-					errmsg("cannot enable failover for a replication slot that enables two-phase decoding"));
+					errmsg("failover and two_phase are mutually exclusive options"));
 	}
 
 	/*
@@ -873,7 +873,7 @@ ReplicationSlotAlter(const char *name, bool failover)
 	if (failover && MyReplicationSlot->data.two_phase)
 		ereport(ERROR,
 				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-				errmsg("cannot enable failover for a replication slot that enables two-phase decoding"));
+				errmsg("cannot enable failover for a two-phase enabled replication slot"));
 
 	if (MyReplicationSlot->data.failover != failover)
 	{


^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* RE: Fix slot synchronization with two_phase decoding enabled
@ 2025-04-01 10:58  Zhijie Hou (Fujitsu) <[email protected]>
  parent: Amit Kapila <[email protected]>
  0 siblings, 1 reply; 88+ messages in thread

From: Zhijie Hou (Fujitsu) @ 2025-04-01 10:58 UTC (permalink / raw)
  To: Amit Kapila <[email protected]>; +Cc: PostgreSQL Hackers <[email protected]>; Hayato Kuroda (Fujitsu) <[email protected]>

On Tue, Apr 1, 2025 at 2:09 PM Amit Kapila wrote:

> 
> On Mon, Mar 31, 2025 at 5:0 PM Zhijie Hou (Fujitsu) 
> <[email protected]> wrote:
> >
> > Thanks for the comments, they have been addressed in V2.
> >
> 
> In the PG17 patch, we only have a check preventing failover and 
> two_phase in CreateSubscription. Don't we need a similar check for AlterSubscription?
> 
> Apart from the above, I have a few suggestions for changes in docs, 
> error messages, and comments for both versions. See attached.

Thanks for the comments.

Here is the V3 patch set which addressed all the comments.

I also added a testcase for ALTER SUB in 0002 as suggested by
Kuroda-san off-list.

Additionally, I found that a test failed in PG17 following this
patch because it involved creating a subscription with both failover and
two-phase enabled. Since that test was designed to test the upgrade of
replication slots and is not directly related to failover functionality, I
decided to disable the failover option for test case.

Best Regards,
Hou zj

From 0c9a8086913ca2e13106df386544821f39c1d41c Mon Sep 17 00:00:00 2001
From: Hou Zhijie <[email protected]>
Date: Mon, 31 Mar 2025 16:28:57 +0800
Subject: [PATCH v3] Disallow enabling failover for a replication slot that
 enables two-phase decoding

This commit fixes a bug for slot synchronization with logical replication
slots that enabled two_phase decoding. As it stands, transactions prepared
before two-phase decoding is enabled may fail to replicate to the subscriber
after being committed on a promoted standby following a failover.

The issue arises because the two_phase_at field of a slot, which tracks the LSN
from which two-phase decoding starts, is not synchronized to standby servers.
Without this field, the logical decoding might incorrectly identify prepared
transaction as already replicated to the subscriber, causing them to be
skipped.

To address the issue on HEAD, this commit makes the two_phase_at field of the slot
visible in the pg_replication_slots view and enables the slot synchronization
to copy this value to the corresponding synced slot on the standby server.

The bug has been present since the introduction of slot synchronization in
PostgreSQL 17. However, due to the need for catalog changes, backpatching this
fix is not feasible. Instead, to prevent the risk of losing prepared
transactions in prior versions, we now disallow enabling failover and two-phase
decoding together for a replication slot.
---
 contrib/test_decoding/expected/slot.out       |  2 ++
 contrib/test_decoding/sql/slot.sql            |  1 +
 src/backend/commands/subscriptioncmds.c       | 25 +++++++++++++++++
 src/backend/replication/slot.c                | 28 +++++++++++++++++++
 src/bin/pg_upgrade/t/003_logical_slots.pl     |  6 ++--
 .../t/040_standby_failover_slots_sync.pl      | 23 +++++++++++++++
 src/test/regress/expected/subscription.out    |  3 ++
 src/test/regress/sql/subscription.sql         |  4 +++
 8 files changed, 89 insertions(+), 3 deletions(-)

diff --git a/contrib/test_decoding/expected/slot.out b/contrib/test_decoding/expected/slot.out
index 7de03c79f6f..8fd762dea85 100644
--- a/contrib/test_decoding/expected/slot.out
+++ b/contrib/test_decoding/expected/slot.out
@@ -427,6 +427,8 @@ SELECT 'init' FROM pg_create_logical_replication_slot('failover_default_slot', '
 
 SELECT 'init' FROM pg_create_logical_replication_slot('failover_true_temp_slot', 'test_decoding', true, false, true);
 ERROR:  cannot enable failover for a temporary replication slot
+SELECT 'init' FROM pg_create_logical_replication_slot('failover_twophase_true_slot', 'test_decoding', false, true, true);
+ERROR:  "failover" and "two_phase" are mutually exclusive options
 SELECT 'init' FROM pg_create_physical_replication_slot('physical_slot');
  ?column? 
 ----------
diff --git a/contrib/test_decoding/sql/slot.sql b/contrib/test_decoding/sql/slot.sql
index 580e3ae3bef..a89fe712ff6 100644
--- a/contrib/test_decoding/sql/slot.sql
+++ b/contrib/test_decoding/sql/slot.sql
@@ -182,6 +182,7 @@ SELECT 'init' FROM pg_create_logical_replication_slot('failover_true_slot', 'tes
 SELECT 'init' FROM pg_create_logical_replication_slot('failover_false_slot', 'test_decoding', false, false, false);
 SELECT 'init' FROM pg_create_logical_replication_slot('failover_default_slot', 'test_decoding', false, false);
 SELECT 'init' FROM pg_create_logical_replication_slot('failover_true_temp_slot', 'test_decoding', true, false, true);
+SELECT 'init' FROM pg_create_logical_replication_slot('failover_twophase_true_slot', 'test_decoding', false, true, true);
 SELECT 'init' FROM pg_create_physical_replication_slot('physical_slot');
 
 SELECT slot_name, slot_type, failover FROM pg_replication_slots;
diff --git a/src/backend/commands/subscriptioncmds.c b/src/backend/commands/subscriptioncmds.c
index 9467f58a23d..6db3c9347fa 100644
--- a/src/backend/commands/subscriptioncmds.c
+++ b/src/backend/commands/subscriptioncmds.c
@@ -648,6 +648,18 @@ CreateSubscription(ParseState *pstate, CreateSubscriptionStmt *stmt,
 				 errmsg("password_required=false is superuser-only"),
 				 errhint("Subscriptions with the password_required option set to false may only be created or modified by the superuser.")));
 
+	/*
+	 * Do not allow users to enable failover and two_phase option together.
+	 *
+	 * See comments atop the similar check in ReplicationSlotCreate() for
+	 * detailed reasons.
+	 */
+	if (opts.twophase && opts.failover)
+		ereport(ERROR,
+				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				errmsg("\"%s\" and \"%s\" are mutually exclusive options",
+					   "failover", "two_phase"));
+
 	/*
 	 * If built with appropriate switch, whine when regression-testing
 	 * conventions for subscription names are violated.
@@ -1245,6 +1257,19 @@ AlterSubscription(ParseState *pstate, AlterSubscriptionStmt *stmt,
 								 errmsg("cannot set %s for enabled subscription",
 										"failover")));
 
+					/*
+					 * Do not allow users to enable failover and two_phase
+					 * option together.
+					 *
+					 * See comments atop the similar check in
+					 * ReplicationSlotCreate() for detailed reasons.
+					 */
+					if (sub->twophasestate != LOGICALREP_TWOPHASE_STATE_DISABLED &&
+						opts.failover)
+						ereport(ERROR,
+								errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+								errmsg("cannot enable failover for a two_phase enabled subscription"));
+
 					/*
 					 * The changed failover option of the slot can't be rolled
 					 * back.
diff --git a/src/backend/replication/slot.c b/src/backend/replication/slot.c
index a1d4768623f..f40028bd941 100644
--- a/src/backend/replication/slot.c
+++ b/src/backend/replication/slot.c
@@ -343,6 +343,22 @@ ReplicationSlotCreate(const char *name, bool db_specific,
 			ereport(ERROR,
 					errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 					errmsg("cannot enable failover for a temporary replication slot"));
+
+		/*
+		 * Do not allow users to enable failover for slots that enable
+		 * two-phase decoding.
+		 *
+		 * This is because the two_phase_at field of a slot, which tracks the
+		 * LSN from which two-phase decoding starts, is not synchronized to
+		 * standby servers. Without this field, the logical decoding might
+		 * incorrectly identify prepared transaction as already replicated to
+		 * the subscriber, causing them to be skipped.
+		 */
+		if (two_phase)
+			ereport(ERROR,
+					errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+					errmsg("\"%s\" and \"%s\" are mutually exclusive options",
+						   "failover", "two_phase"));
 	}
 
 	/*
@@ -848,6 +864,18 @@ ReplicationSlotAlter(const char *name, bool failover)
 				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				errmsg("cannot enable failover for a temporary replication slot"));
 
+	/*
+	 * Do not allow users to enable failover for slots that enable two-phase
+	 * decoding.
+	 *
+	 * See comments atop the similar check in ReplicationSlotCreate() for
+	 * detailed reasons.
+	 */
+	if (failover && MyReplicationSlot->data.two_phase)
+		ereport(ERROR,
+				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				errmsg("cannot enable failover for a two-phase enabled replication slot"));
+
 	if (MyReplicationSlot->data.failover != failover)
 	{
 		SpinLockAcquire(&MyReplicationSlot->mutex);
diff --git a/src/bin/pg_upgrade/t/003_logical_slots.pl b/src/bin/pg_upgrade/t/003_logical_slots.pl
index 0a2483d3dfc..e329cc609ce 100644
--- a/src/bin/pg_upgrade/t/003_logical_slots.pl
+++ b/src/bin/pg_upgrade/t/003_logical_slots.pl
@@ -173,7 +173,7 @@ $sub->start;
 $sub->safe_psql(
 	'postgres', qq[
 	CREATE TABLE tbl (a int);
-	CREATE SUBSCRIPTION regress_sub CONNECTION '$old_connstr' PUBLICATION regress_pub WITH (two_phase = 'true', failover = 'true')
+	CREATE SUBSCRIPTION regress_sub CONNECTION '$old_connstr' PUBLICATION regress_pub WITH (two_phase = 'true')
 ]);
 $sub->wait_for_subscription_sync($oldpub, 'regress_sub');
 
@@ -193,8 +193,8 @@ command_ok([@pg_upgrade_cmd], 'run of pg_upgrade of old cluster');
 # Check that the slot 'regress_sub' has migrated to the new cluster
 $newpub->start;
 my $result = $newpub->safe_psql('postgres',
-	"SELECT slot_name, two_phase, failover FROM pg_replication_slots");
-is($result, qq(regress_sub|t|t), 'check the slot exists on new cluster');
+	"SELECT slot_name, two_phase FROM pg_replication_slots");
+is($result, qq(regress_sub|t), 'check the slot exists on new cluster');
 
 # Update the connection
 my $new_connstr = $newpub->connstr . ' dbname=postgres';
diff --git a/src/test/recovery/t/040_standby_failover_slots_sync.pl b/src/test/recovery/t/040_standby_failover_slots_sync.pl
index 823857bb329..6e68ed5d4bb 100644
--- a/src/test/recovery/t/040_standby_failover_slots_sync.pl
+++ b/src/test/recovery/t/040_standby_failover_slots_sync.pl
@@ -98,6 +98,29 @@ my ($result, $stdout, $stderr) = $subscriber1->psql('postgres',
 ok( $stderr =~ /ERROR:  cannot set failover for enabled subscription/,
 	"altering failover is not allowed for enabled subscription");
 
+##################################################
+# Test that the failover option cannot be enabled for a two_phase enabled
+# subscription.
+##################################################
+
+# Create a subscription with two_phase enabled
+$subscriber1->safe_psql('postgres',
+	"CREATE SUBSCRIPTION regress_mysub2 CONNECTION '$publisher_connstr' PUBLICATION regress_mypub WITH (slot_name = lsub1_slot, create_slot = false, enabled = false, two_phase = true);"
+);
+
+# Enable failover for the subscription
+($result, $stdout, $stderr) = $subscriber1->psql('postgres',
+	"ALTER SUBSCRIPTION regress_mysub2 SET (failover = true)");
+ok( $stderr =~ /ERROR:  cannot enable failover for a two_phase enabled subscription/,
+	"Enabling failover is not allowed for a two_phase enabled subscription");
+
+# Drop the subscription
+$subscriber1->safe_psql(
+	'postgres', q{
+ALTER SUBSCRIPTION regress_mysub2 SET (slot_name = NONE);
+DROP SUBSCRIPTION regress_mysub2;
+});
+
 ##################################################
 # Test that pg_sync_replication_slots() cannot be executed on a non-standby server.
 ##################################################
diff --git a/src/test/regress/expected/subscription.out b/src/test/regress/expected/subscription.out
index 0f2a25cdc19..bbd83244ba9 100644
--- a/src/test/regress/expected/subscription.out
+++ b/src/test/regress/expected/subscription.out
@@ -479,6 +479,9 @@ COMMIT;
 ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
 DROP SUBSCRIPTION regress_testsub;
 RESET SESSION AUTHORIZATION;
+-- fail - cannot enable two_phase and failover together
+CREATE SUBSCRIPTION regress_testsub CONNECTION 'dbname=regress_doesnotexist' PUBLICATION testpub WITH (connect = false, two_phase = true, failover = true);
+ERROR:  "failover" and "two_phase" are mutually exclusive options
 DROP ROLE regress_subscription_user;
 DROP ROLE regress_subscription_user2;
 DROP ROLE regress_subscription_user3;
diff --git a/src/test/regress/sql/subscription.sql b/src/test/regress/sql/subscription.sql
index 3e5ba4cb8c6..47fc1e5329b 100644
--- a/src/test/regress/sql/subscription.sql
+++ b/src/test/regress/sql/subscription.sql
@@ -342,6 +342,10 @@ ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
 DROP SUBSCRIPTION regress_testsub;
 
 RESET SESSION AUTHORIZATION;
+
+-- fail - cannot enable two_phase and failover together
+CREATE SUBSCRIPTION regress_testsub CONNECTION 'dbname=regress_doesnotexist' PUBLICATION testpub WITH (connect = false, two_phase = true, failover = true);
+
 DROP ROLE regress_subscription_user;
 DROP ROLE regress_subscription_user2;
 DROP ROLE regress_subscription_user3;
-- 
2.30.0.windows.2



Attachments:

  [application/octet-stream] v3-0001-Fix-slot-synchronization-with-two_phase-decoding-.patch (14.2K, ../../OS3PR01MB5718390A647E7789161815CD94AC2@OS3PR01MB5718.jpnprd01.prod.outlook.com/2-v3-0001-Fix-slot-synchronization-with-two_phase-decoding-.patch)
  download | inline diff:
From cace883386387f9c4702fe0457e288aa3d5b2559 Mon Sep 17 00:00:00 2001
From: Hou Zhijie <[email protected]>
Date: Thu, 27 Feb 2025 10:49:32 +0800
Subject: [PATCH v3] Fix slot synchronization with two_phase decoding enabled

This commit fixes a bug for slot synchronization with logical replication
slots that enabled two_phase decoding. As it stands, transactions prepared
before two-phase decoding is enabled may fail to replicate to the subscriber
after being committed on a promoted standby following a failover.

The issue arises because the two_phase_at field of a slot, which tracks the LSN
from which two-phase decoding starts, is not synchronized to standby servers.
Without this field, the logical decoding might incorrectly identify prepared
transaction as already replicated to the subscriber, causing them to be
skipped.

To address the issue on HEAD, this commit makes the two_phase_at field of the slot
visible in the pg_replication_slots view and enables the slot synchronization
to copy this value to the corresponding synced slot on the standby server.

The bug has been present since the introduction of slot synchronization in
PostgreSQL 17. However, due to the need for catalog changes, backpatching this
fix is not feasible. Instead, to prevent the risk of losing prepared
transactions in prior versions, we now disallow enabling failover and two-phase
decoding together for a replication slot.
---
 doc/src/sgml/system-views.sgml                | 11 +++
 src/backend/catalog/system_views.sql          |  1 +
 src/backend/replication/logical/slotsync.c    | 14 +++-
 src/backend/replication/slotfuncs.c           |  8 +-
 src/include/catalog/pg_proc.dat               |  6 +-
 .../t/040_standby_failover_slots_sync.pl      | 81 ++++++++++++++++++-
 src/test/regress/expected/rules.out           |  3 +-
 7 files changed, 111 insertions(+), 13 deletions(-)

diff --git a/doc/src/sgml/system-views.sgml b/doc/src/sgml/system-views.sgml
index 3f5a306247e..5c9425e6d1f 100644
--- a/doc/src/sgml/system-views.sgml
+++ b/doc/src/sgml/system-views.sgml
@@ -2560,6 +2560,17 @@ SELECT * FROM pg_locks pl LEFT JOIN pg_prepared_xacts ppx
       </para></entry>
      </row>
 
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>two_phase_at</structfield> <type>pg_lsn</type>
+      </para>
+      <para>
+       The address (<literal>LSN</literal>) from which the decoding of prepared
+       transactions is enabled. <literal>NULL</literal> for logical slots where
+       <structfield>two_phase</structfield> is false and physical slots.
+      </para></entry>
+     </row>
+
      <row>
       <entry role="catalog_table_entry"><para role="column_definition">
        <structfield>inactive_since</structfield> <type>timestamptz</type>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 31d269b7ee0..a8fddd0183c 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -1025,6 +1025,7 @@ CREATE VIEW pg_replication_slots AS
             L.wal_status,
             L.safe_wal_size,
             L.two_phase,
+            L.two_phase_at,
             L.inactive_since,
             L.conflicting,
             L.invalidation_reason,
diff --git a/src/backend/replication/logical/slotsync.c b/src/backend/replication/logical/slotsync.c
index 2c0a7439be4..e22d41891e6 100644
--- a/src/backend/replication/logical/slotsync.c
+++ b/src/backend/replication/logical/slotsync.c
@@ -139,6 +139,7 @@ typedef struct RemoteSlot
 	bool		failover;
 	XLogRecPtr	restart_lsn;
 	XLogRecPtr	confirmed_lsn;
+	XLogRecPtr	two_phase_at;
 	TransactionId catalog_xmin;
 
 	/* RS_INVAL_NONE if valid, or the reason of invalidation */
@@ -276,7 +277,8 @@ update_local_synced_slot(RemoteSlot *remote_slot, Oid remote_dbid,
 	if (remote_dbid != slot->data.database ||
 		remote_slot->two_phase != slot->data.two_phase ||
 		remote_slot->failover != slot->data.failover ||
-		strcmp(remote_slot->plugin, NameStr(slot->data.plugin)) != 0)
+		strcmp(remote_slot->plugin, NameStr(slot->data.plugin)) != 0 ||
+		remote_slot->two_phase_at != slot->data.two_phase_at)
 	{
 		NameData	plugin_name;
 
@@ -287,6 +289,7 @@ update_local_synced_slot(RemoteSlot *remote_slot, Oid remote_dbid,
 		slot->data.plugin = plugin_name;
 		slot->data.database = remote_dbid;
 		slot->data.two_phase = remote_slot->two_phase;
+		slot->data.two_phase_at = remote_slot->two_phase_at;
 		slot->data.failover = remote_slot->failover;
 		SpinLockRelease(&slot->mutex);
 
@@ -788,9 +791,9 @@ synchronize_one_slot(RemoteSlot *remote_slot, Oid remote_dbid)
 static bool
 synchronize_slots(WalReceiverConn *wrconn)
 {
-#define SLOTSYNC_COLUMN_COUNT 9
+#define SLOTSYNC_COLUMN_COUNT 10
 	Oid			slotRow[SLOTSYNC_COLUMN_COUNT] = {TEXTOID, TEXTOID, LSNOID,
-	LSNOID, XIDOID, BOOLOID, BOOLOID, TEXTOID, TEXTOID};
+	LSNOID, XIDOID, BOOLOID, LSNOID, BOOLOID, TEXTOID, TEXTOID};
 
 	WalRcvExecResult *res;
 	TupleTableSlot *tupslot;
@@ -798,7 +801,7 @@ synchronize_slots(WalReceiverConn *wrconn)
 	bool		some_slot_updated = false;
 	bool		started_tx = false;
 	const char *query = "SELECT slot_name, plugin, confirmed_flush_lsn,"
-		" restart_lsn, catalog_xmin, two_phase, failover,"
+		" restart_lsn, catalog_xmin, two_phase, two_phase_at, failover,"
 		" database, invalidation_reason"
 		" FROM pg_catalog.pg_replication_slots"
 		" WHERE failover and NOT temporary";
@@ -853,6 +856,9 @@ synchronize_slots(WalReceiverConn *wrconn)
 														   &isnull));
 		Assert(!isnull);
 
+		d = slot_getattr(tupslot, ++col, &isnull);
+		remote_slot->two_phase_at = isnull ? InvalidXLogRecPtr : DatumGetLSN(d);
+
 		remote_slot->failover = DatumGetBool(slot_getattr(tupslot, ++col,
 														  &isnull));
 		Assert(!isnull);
diff --git a/src/backend/replication/slotfuncs.c b/src/backend/replication/slotfuncs.c
index 146eef5871e..8a314b5ff3b 100644
--- a/src/backend/replication/slotfuncs.c
+++ b/src/backend/replication/slotfuncs.c
@@ -235,7 +235,7 @@ pg_drop_replication_slot(PG_FUNCTION_ARGS)
 Datum
 pg_get_replication_slots(PG_FUNCTION_ARGS)
 {
-#define PG_GET_REPLICATION_SLOTS_COLS 19
+#define PG_GET_REPLICATION_SLOTS_COLS 20
 	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
 	XLogRecPtr	currlsn;
 	int			slotno;
@@ -406,6 +406,12 @@ pg_get_replication_slots(PG_FUNCTION_ARGS)
 
 		values[i++] = BoolGetDatum(slot_contents.data.two_phase);
 
+		if (slot_contents.data.two_phase &&
+			!XLogRecPtrIsInvalid(slot_contents.data.two_phase_at))
+			values[i++] = LSNGetDatum(slot_contents.data.two_phase_at);
+		else
+			nulls[i++] = true;
+
 		if (slot_contents.inactive_since > 0)
 			values[i++] = TimestampTzGetDatum(slot_contents.inactive_since);
 		else
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 8b68b16d79d..a89488419a6 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -11409,9 +11409,9 @@
   proname => 'pg_get_replication_slots', prorows => '10', proisstrict => 'f',
   proretset => 't', provolatile => 's', prorettype => 'record',
   proargtypes => '',
-  proallargtypes => '{name,name,text,oid,bool,bool,int4,xid,xid,pg_lsn,pg_lsn,text,int8,bool,timestamptz,bool,text,bool,bool}',
-  proargmodes => '{o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
-  proargnames => '{slot_name,plugin,slot_type,datoid,temporary,active,active_pid,xmin,catalog_xmin,restart_lsn,confirmed_flush_lsn,wal_status,safe_wal_size,two_phase,inactive_since,conflicting,invalidation_reason,failover,synced}',
+  proallargtypes => '{name,name,text,oid,bool,bool,int4,xid,xid,pg_lsn,pg_lsn,text,int8,bool,pg_lsn,timestamptz,bool,text,bool,bool}',
+  proargmodes => '{o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{slot_name,plugin,slot_type,datoid,temporary,active,active_pid,xmin,catalog_xmin,restart_lsn,confirmed_flush_lsn,wal_status,safe_wal_size,two_phase,two_phase_at,inactive_since,conflicting,invalidation_reason,failover,synced}',
   prosrc => 'pg_get_replication_slots' },
 { oid => '3786', descr => 'set up a logical replication slot',
   proname => 'pg_create_logical_replication_slot', provolatile => 'v',
diff --git a/src/test/recovery/t/040_standby_failover_slots_sync.pl b/src/test/recovery/t/040_standby_failover_slots_sync.pl
index 8f65142909a..9c8b49e942d 100644
--- a/src/test/recovery/t/040_standby_failover_slots_sync.pl
+++ b/src/test/recovery/t/040_standby_failover_slots_sync.pl
@@ -22,7 +22,11 @@ $publisher->init(
 # Disable autovacuum to avoid generating xid during stats update as otherwise
 # the new XID could then be replicated to standby at some random point making
 # slots at primary lag behind standby during slot sync.
-$publisher->append_conf('postgresql.conf', 'autovacuum = off');
+$publisher->append_conf(
+	'postgresql.conf', qq{
+autovacuum = off
+max_prepared_transactions = 1
+});
 $publisher->start;
 
 $publisher->safe_psql('postgres',
@@ -33,6 +37,7 @@ my $publisher_connstr = $publisher->connstr . ' dbname=postgres';
 # Create a subscriber node, wait for sync to complete
 my $subscriber1 = PostgreSQL::Test::Cluster->new('subscriber1');
 $subscriber1->init;
+$subscriber1->append_conf('postgresql.conf', 'max_prepared_transactions = 1');
 $subscriber1->start;
 
 # Capture the time before the logical failover slot is created on the
@@ -830,13 +835,72 @@ $primary->adjust_conf('postgresql.conf', 'synchronized_standby_slots',
 	"'sb1_slot'");
 $primary->reload;
 
+##################################################
+# Test the synchronization of the two_phase setting for a subscription with the
+# standby. Additionally, prepare a transaction before enabling the two_phase
+# option; subsequent tests will verify if it can be correctly replicated to the
+# subscriber after committing it on the promoted standby.
+##################################################
+
+$standby1->start;
+
+# Prepare a transaction
+$primary->safe_psql(
+	'postgres', qq[
+	BEGIN;
+	INSERT INTO tab_int values(0);
+	PREPARE TRANSACTION 'test_twophase_slotsync';
+]);
+
+$primary->wait_for_replay_catchup($standby1);
+$primary->wait_for_catchup('regress_mysub1');
+
+# Disable the subscription to allow changing the two_phase option.
+$subscriber1->safe_psql('postgres',
+	"ALTER SUBSCRIPTION regress_mysub1 DISABLE");
+
+# Wait for the replication slot to become inactive on the publisher
+$primary->poll_query_until(
+	'postgres',
+	"SELECT COUNT(*) FROM pg_catalog.pg_replication_slots WHERE slot_name = 'lsub1_slot' AND active='f'",
+	1);
+
+# Set two_phase to true and enable the subscription
+$subscriber1->safe_psql(
+	'postgres', qq[
+	ALTER SUBSCRIPTION regress_mysub1 SET (two_phase = true);
+	ALTER SUBSCRIPTION regress_mysub1 ENABLE;
+]);
+
+$primary->wait_for_catchup('regress_mysub1');
+
+my $two_phase_at = $primary->safe_psql('postgres',
+	"SELECT two_phase_at from pg_replication_slots WHERE slot_name = 'lsub1_slot';"
+);
+
+# Confirm that two_phase setting of lsub1_slot slot is synced to the standby
+ok( $standby1->poll_query_until(
+		'postgres',
+		"SELECT two_phase AND '$two_phase_at' = two_phase_at from pg_replication_slots WHERE slot_name = 'lsub1_slot' AND synced AND NOT temporary;"
+	),
+	'two_phase setting of slot lsub1_slot synced to standby');
+
+# Confirm that the prepared transaction is not yet replicated to the
+# subscriber.
+$result = $subscriber1->safe_psql('postgres',
+	"SELECT count(*) = 0 FROM pg_prepared_xacts;");
+is($result, 't',
+	"the prepared transaction is not replicated to the subscriber");
+
 ##################################################
 # Promote the standby1 to primary. Confirm that:
 # a) the slot 'lsub1_slot' and 'snap_test_slot' are retained on the new primary
 # b) logical replication for regress_mysub1 is resumed successfully after failover
-# c) changes can be consumed from the synced slot 'snap_test_slot'
+# c) changes from the transaction prepared 'test_twophase_slotsync' can be
+#    consumed from the synced slot 'snap_test_slot' once committed on the new
+#    primary.
+# d) changes can be consumed from the synced slot 'snap_test_slot'
 ##################################################
-$standby1->start;
 $primary->wait_for_replay_catchup($standby1);
 
 # Capture the time before the standby is promoted
@@ -876,6 +940,15 @@ is( $standby1->safe_psql(
 	't',
 	'synced slot retained on the new primary');
 
+# Commit the prepared transaction
+$standby1->safe_psql('postgres',
+	"COMMIT PREPARED 'test_twophase_slotsync';");
+$standby1->wait_for_catchup('regress_mysub1');
+
+# Confirm that the prepared transaction is replicated to the subscriber
+is($subscriber1->safe_psql('postgres', q{SELECT count(*) FROM tab_int;}),
+	"11", 'prepared data replicated from the new primary');
+
 # Insert data on the new primary
 $standby1->safe_psql('postgres',
 	"INSERT INTO tab_int SELECT generate_series(11, 20);");
@@ -883,7 +956,7 @@ $standby1->wait_for_catchup('regress_mysub1');
 
 # Confirm that data in tab_int replicated on the subscriber
 is($subscriber1->safe_psql('postgres', q{SELECT count(*) FROM tab_int;}),
-	"20", 'data replicated from the new primary');
+	"21", 'data replicated from the new primary');
 
 # Consume the data from the snap_test_slot. The synced slot should reach a
 # consistent point by restoring the snapshot at the restart_lsn serialized
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 47478969135..035769b4624 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1474,12 +1474,13 @@ pg_replication_slots| SELECT l.slot_name,
     l.wal_status,
     l.safe_wal_size,
     l.two_phase,
+    l.two_phase_at,
     l.inactive_since,
     l.conflicting,
     l.invalidation_reason,
     l.failover,
     l.synced
-   FROM (pg_get_replication_slots() l(slot_name, plugin, slot_type, datoid, temporary, active, active_pid, xmin, catalog_xmin, restart_lsn, confirmed_flush_lsn, wal_status, safe_wal_size, two_phase, inactive_since, conflicting, invalidation_reason, failover, synced)
+   FROM (pg_get_replication_slots() l(slot_name, plugin, slot_type, datoid, temporary, active, active_pid, xmin, catalog_xmin, restart_lsn, confirmed_flush_lsn, wal_status, safe_wal_size, two_phase, two_phase_at, inactive_since, conflicting, invalidation_reason, failover, synced)
      LEFT JOIN pg_database d ON ((l.datoid = d.oid)));
 pg_roles| SELECT pg_authid.rolname,
     pg_authid.rolsuper,
-- 
2.30.0.windows.2



  [text/plain] v3-0002-PG-Disallow-enabling-failover-for-a-replication-slot.patch.txt (11.3K, ../../OS3PR01MB5718390A647E7789161815CD94AC2@OS3PR01MB5718.jpnprd01.prod.outlook.com/3-v3-0002-PG-Disallow-enabling-failover-for-a-replication-slot.patch.txt)
  download | inline diff:
From 0c9a8086913ca2e13106df386544821f39c1d41c Mon Sep 17 00:00:00 2001
From: Hou Zhijie <[email protected]>
Date: Mon, 31 Mar 2025 16:28:57 +0800
Subject: [PATCH v3] Disallow enabling failover for a replication slot that
 enables two-phase decoding

This commit fixes a bug for slot synchronization with logical replication
slots that enabled two_phase decoding. As it stands, transactions prepared
before two-phase decoding is enabled may fail to replicate to the subscriber
after being committed on a promoted standby following a failover.

The issue arises because the two_phase_at field of a slot, which tracks the LSN
from which two-phase decoding starts, is not synchronized to standby servers.
Without this field, the logical decoding might incorrectly identify prepared
transaction as already replicated to the subscriber, causing them to be
skipped.

To address the issue on HEAD, this commit makes the two_phase_at field of the slot
visible in the pg_replication_slots view and enables the slot synchronization
to copy this value to the corresponding synced slot on the standby server.

The bug has been present since the introduction of slot synchronization in
PostgreSQL 17. However, due to the need for catalog changes, backpatching this
fix is not feasible. Instead, to prevent the risk of losing prepared
transactions in prior versions, we now disallow enabling failover and two-phase
decoding together for a replication slot.
---
 contrib/test_decoding/expected/slot.out       |  2 ++
 contrib/test_decoding/sql/slot.sql            |  1 +
 src/backend/commands/subscriptioncmds.c       | 25 +++++++++++++++++
 src/backend/replication/slot.c                | 28 +++++++++++++++++++
 src/bin/pg_upgrade/t/003_logical_slots.pl     |  6 ++--
 .../t/040_standby_failover_slots_sync.pl      | 23 +++++++++++++++
 src/test/regress/expected/subscription.out    |  3 ++
 src/test/regress/sql/subscription.sql         |  4 +++
 8 files changed, 89 insertions(+), 3 deletions(-)

diff --git a/contrib/test_decoding/expected/slot.out b/contrib/test_decoding/expected/slot.out
index 7de03c79f6f..8fd762dea85 100644
--- a/contrib/test_decoding/expected/slot.out
+++ b/contrib/test_decoding/expected/slot.out
@@ -427,6 +427,8 @@ SELECT 'init' FROM pg_create_logical_replication_slot('failover_default_slot', '
 
 SELECT 'init' FROM pg_create_logical_replication_slot('failover_true_temp_slot', 'test_decoding', true, false, true);
 ERROR:  cannot enable failover for a temporary replication slot
+SELECT 'init' FROM pg_create_logical_replication_slot('failover_twophase_true_slot', 'test_decoding', false, true, true);
+ERROR:  "failover" and "two_phase" are mutually exclusive options
 SELECT 'init' FROM pg_create_physical_replication_slot('physical_slot');
  ?column? 
 ----------
diff --git a/contrib/test_decoding/sql/slot.sql b/contrib/test_decoding/sql/slot.sql
index 580e3ae3bef..a89fe712ff6 100644
--- a/contrib/test_decoding/sql/slot.sql
+++ b/contrib/test_decoding/sql/slot.sql
@@ -182,6 +182,7 @@ SELECT 'init' FROM pg_create_logical_replication_slot('failover_true_slot', 'tes
 SELECT 'init' FROM pg_create_logical_replication_slot('failover_false_slot', 'test_decoding', false, false, false);
 SELECT 'init' FROM pg_create_logical_replication_slot('failover_default_slot', 'test_decoding', false, false);
 SELECT 'init' FROM pg_create_logical_replication_slot('failover_true_temp_slot', 'test_decoding', true, false, true);
+SELECT 'init' FROM pg_create_logical_replication_slot('failover_twophase_true_slot', 'test_decoding', false, true, true);
 SELECT 'init' FROM pg_create_physical_replication_slot('physical_slot');
 
 SELECT slot_name, slot_type, failover FROM pg_replication_slots;
diff --git a/src/backend/commands/subscriptioncmds.c b/src/backend/commands/subscriptioncmds.c
index 9467f58a23d..6db3c9347fa 100644
--- a/src/backend/commands/subscriptioncmds.c
+++ b/src/backend/commands/subscriptioncmds.c
@@ -648,6 +648,18 @@ CreateSubscription(ParseState *pstate, CreateSubscriptionStmt *stmt,
 				 errmsg("password_required=false is superuser-only"),
 				 errhint("Subscriptions with the password_required option set to false may only be created or modified by the superuser.")));
 
+	/*
+	 * Do not allow users to enable failover and two_phase option together.
+	 *
+	 * See comments atop the similar check in ReplicationSlotCreate() for
+	 * detailed reasons.
+	 */
+	if (opts.twophase && opts.failover)
+		ereport(ERROR,
+				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				errmsg("\"%s\" and \"%s\" are mutually exclusive options",
+					   "failover", "two_phase"));
+
 	/*
 	 * If built with appropriate switch, whine when regression-testing
 	 * conventions for subscription names are violated.
@@ -1245,6 +1257,19 @@ AlterSubscription(ParseState *pstate, AlterSubscriptionStmt *stmt,
 								 errmsg("cannot set %s for enabled subscription",
 										"failover")));
 
+					/*
+					 * Do not allow users to enable failover and two_phase
+					 * option together.
+					 *
+					 * See comments atop the similar check in
+					 * ReplicationSlotCreate() for detailed reasons.
+					 */
+					if (sub->twophasestate != LOGICALREP_TWOPHASE_STATE_DISABLED &&
+						opts.failover)
+						ereport(ERROR,
+								errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+								errmsg("cannot enable failover for a two_phase enabled subscription"));
+
 					/*
 					 * The changed failover option of the slot can't be rolled
 					 * back.
diff --git a/src/backend/replication/slot.c b/src/backend/replication/slot.c
index a1d4768623f..f40028bd941 100644
--- a/src/backend/replication/slot.c
+++ b/src/backend/replication/slot.c
@@ -343,6 +343,22 @@ ReplicationSlotCreate(const char *name, bool db_specific,
 			ereport(ERROR,
 					errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 					errmsg("cannot enable failover for a temporary replication slot"));
+
+		/*
+		 * Do not allow users to enable failover for slots that enable
+		 * two-phase decoding.
+		 *
+		 * This is because the two_phase_at field of a slot, which tracks the
+		 * LSN from which two-phase decoding starts, is not synchronized to
+		 * standby servers. Without this field, the logical decoding might
+		 * incorrectly identify prepared transaction as already replicated to
+		 * the subscriber, causing them to be skipped.
+		 */
+		if (two_phase)
+			ereport(ERROR,
+					errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+					errmsg("\"%s\" and \"%s\" are mutually exclusive options",
+						   "failover", "two_phase"));
 	}
 
 	/*
@@ -848,6 +864,18 @@ ReplicationSlotAlter(const char *name, bool failover)
 				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				errmsg("cannot enable failover for a temporary replication slot"));
 
+	/*
+	 * Do not allow users to enable failover for slots that enable two-phase
+	 * decoding.
+	 *
+	 * See comments atop the similar check in ReplicationSlotCreate() for
+	 * detailed reasons.
+	 */
+	if (failover && MyReplicationSlot->data.two_phase)
+		ereport(ERROR,
+				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				errmsg("cannot enable failover for a two-phase enabled replication slot"));
+
 	if (MyReplicationSlot->data.failover != failover)
 	{
 		SpinLockAcquire(&MyReplicationSlot->mutex);
diff --git a/src/bin/pg_upgrade/t/003_logical_slots.pl b/src/bin/pg_upgrade/t/003_logical_slots.pl
index 0a2483d3dfc..e329cc609ce 100644
--- a/src/bin/pg_upgrade/t/003_logical_slots.pl
+++ b/src/bin/pg_upgrade/t/003_logical_slots.pl
@@ -173,7 +173,7 @@ $sub->start;
 $sub->safe_psql(
 	'postgres', qq[
 	CREATE TABLE tbl (a int);
-	CREATE SUBSCRIPTION regress_sub CONNECTION '$old_connstr' PUBLICATION regress_pub WITH (two_phase = 'true', failover = 'true')
+	CREATE SUBSCRIPTION regress_sub CONNECTION '$old_connstr' PUBLICATION regress_pub WITH (two_phase = 'true')
 ]);
 $sub->wait_for_subscription_sync($oldpub, 'regress_sub');
 
@@ -193,8 +193,8 @@ command_ok([@pg_upgrade_cmd], 'run of pg_upgrade of old cluster');
 # Check that the slot 'regress_sub' has migrated to the new cluster
 $newpub->start;
 my $result = $newpub->safe_psql('postgres',
-	"SELECT slot_name, two_phase, failover FROM pg_replication_slots");
-is($result, qq(regress_sub|t|t), 'check the slot exists on new cluster');
+	"SELECT slot_name, two_phase FROM pg_replication_slots");
+is($result, qq(regress_sub|t), 'check the slot exists on new cluster');
 
 # Update the connection
 my $new_connstr = $newpub->connstr . ' dbname=postgres';
diff --git a/src/test/recovery/t/040_standby_failover_slots_sync.pl b/src/test/recovery/t/040_standby_failover_slots_sync.pl
index 823857bb329..6e68ed5d4bb 100644
--- a/src/test/recovery/t/040_standby_failover_slots_sync.pl
+++ b/src/test/recovery/t/040_standby_failover_slots_sync.pl
@@ -98,6 +98,29 @@ my ($result, $stdout, $stderr) = $subscriber1->psql('postgres',
 ok( $stderr =~ /ERROR:  cannot set failover for enabled subscription/,
 	"altering failover is not allowed for enabled subscription");
 
+##################################################
+# Test that the failover option cannot be enabled for a two_phase enabled
+# subscription.
+##################################################
+
+# Create a subscription with two_phase enabled
+$subscriber1->safe_psql('postgres',
+	"CREATE SUBSCRIPTION regress_mysub2 CONNECTION '$publisher_connstr' PUBLICATION regress_mypub WITH (slot_name = lsub1_slot, create_slot = false, enabled = false, two_phase = true);"
+);
+
+# Enable failover for the subscription
+($result, $stdout, $stderr) = $subscriber1->psql('postgres',
+	"ALTER SUBSCRIPTION regress_mysub2 SET (failover = true)");
+ok( $stderr =~ /ERROR:  cannot enable failover for a two_phase enabled subscription/,
+	"Enabling failover is not allowed for a two_phase enabled subscription");
+
+# Drop the subscription
+$subscriber1->safe_psql(
+	'postgres', q{
+ALTER SUBSCRIPTION regress_mysub2 SET (slot_name = NONE);
+DROP SUBSCRIPTION regress_mysub2;
+});
+
 ##################################################
 # Test that pg_sync_replication_slots() cannot be executed on a non-standby server.
 ##################################################
diff --git a/src/test/regress/expected/subscription.out b/src/test/regress/expected/subscription.out
index 0f2a25cdc19..bbd83244ba9 100644
--- a/src/test/regress/expected/subscription.out
+++ b/src/test/regress/expected/subscription.out
@@ -479,6 +479,9 @@ COMMIT;
 ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
 DROP SUBSCRIPTION regress_testsub;
 RESET SESSION AUTHORIZATION;
+-- fail - cannot enable two_phase and failover together
+CREATE SUBSCRIPTION regress_testsub CONNECTION 'dbname=regress_doesnotexist' PUBLICATION testpub WITH (connect = false, two_phase = true, failover = true);
+ERROR:  "failover" and "two_phase" are mutually exclusive options
 DROP ROLE regress_subscription_user;
 DROP ROLE regress_subscription_user2;
 DROP ROLE regress_subscription_user3;
diff --git a/src/test/regress/sql/subscription.sql b/src/test/regress/sql/subscription.sql
index 3e5ba4cb8c6..47fc1e5329b 100644
--- a/src/test/regress/sql/subscription.sql
+++ b/src/test/regress/sql/subscription.sql
@@ -342,6 +342,10 @@ ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
 DROP SUBSCRIPTION regress_testsub;
 
 RESET SESSION AUTHORIZATION;
+
+-- fail - cannot enable two_phase and failover together
+CREATE SUBSCRIPTION regress_testsub CONNECTION 'dbname=regress_doesnotexist' PUBLICATION testpub WITH (connect = false, two_phase = true, failover = true);
+
 DROP ROLE regress_subscription_user;
 DROP ROLE regress_subscription_user2;
 DROP ROLE regress_subscription_user3;
-- 
2.30.0.windows.2



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* Re: Fix slot synchronization with two_phase decoding enabled
@ 2025-04-02 04:40  Amit Kapila <[email protected]>
  parent: Zhijie Hou (Fujitsu) <[email protected]>
  0 siblings, 1 reply; 88+ messages in thread

From: Amit Kapila @ 2025-04-02 04:40 UTC (permalink / raw)
  To: Zhijie Hou (Fujitsu) <[email protected]>; +Cc: PostgreSQL Hackers <[email protected]>; Hayato Kuroda (Fujitsu) <[email protected]>

On Tue, Apr 1, 2025 at 4:28 PM Zhijie Hou (Fujitsu)
<[email protected]> wrote:
>
> Here is the V3 patch set which addressed all the comments.
>

Comment 0n 0001
<literal>NULL</literal> for logical slots where
+       <structfield>two_phase</structfield> is false and physical slots.
+      </para></entry>

change above to:
<literal>NULL</literal> for logical slots where
<structfield>two_phase</structfield> is false and for physical slots.

Comment on 0002
+# Create a subscription with two_phase enabled
+$subscriber1->safe_psql('postgres',
+ "CREATE SUBSCRIPTION regress_mysub2 CONNECTION '$publisher_connstr'
PUBLICATION regress_mypub WITH (slot_name = lsub1_slot, create_slot =
false, enabled = false, two_phase = true);"
+);
+
+# Enable failover for the subscription
+($result, $stdout, $stderr) = $subscriber1->psql('postgres',
+ "ALTER SUBSCRIPTION regress_mysub2 SET (failover = true)");
+ok( $stderr =~ /ERROR:  cannot enable failover for a two_phase
enabled subscription/,
+ "Enabling failover is not allowed for a two_phase enabled subscription");

Is there a need for this test to be in .pl file? Can't we add it in .sql file?

Apart from the above, I have made minor modifications to the PG17
patch in the attached.

-- 
With Regards,
Amit Kapila.

diff --git a/src/backend/commands/subscriptioncmds.c b/src/backend/commands/subscriptioncmds.c
index 6db3c9347fa..09c5f0ef685 100644
--- a/src/backend/commands/subscriptioncmds.c
+++ b/src/backend/commands/subscriptioncmds.c
@@ -649,10 +649,11 @@ CreateSubscription(ParseState *pstate, CreateSubscriptionStmt *stmt,
 				 errhint("Subscriptions with the password_required option set to false may only be created or modified by the superuser.")));
 
 	/*
-	 * Do not allow users to enable failover and two_phase option together.
+	 * Do not allow users to enable the failover and two_phase options
+	 * together.
 	 *
-	 * See comments atop the similar check in ReplicationSlotCreate() for
-	 * detailed reasons.
+	 * See comments atop the similar check in ReplicationSlotCreate() for a
+	 * detailed reason.
 	 */
 	if (opts.twophase && opts.failover)
 		ereport(ERROR,
@@ -1258,11 +1259,11 @@ AlterSubscription(ParseState *pstate, AlterSubscriptionStmt *stmt,
 										"failover")));
 
 					/*
-					 * Do not allow users to enable failover and two_phase
-					 * option together.
+					 * Do not allow users to enable the failover and two_phase
+					 * options together.
 					 *
 					 * See comments atop the similar check in
-					 * ReplicationSlotCreate() for detailed reasons.
+					 * ReplicationSlotCreate() for a detailed reason.
 					 */
 					if (sub->twophasestate != LOGICALREP_TWOPHASE_STATE_DISABLED &&
 						opts.failover)
diff --git a/src/backend/replication/slot.c b/src/backend/replication/slot.c
index f40028bd941..d251ce95fe6 100644
--- a/src/backend/replication/slot.c
+++ b/src/backend/replication/slot.c
@@ -345,14 +345,14 @@ ReplicationSlotCreate(const char *name, bool db_specific,
 					errmsg("cannot enable failover for a temporary replication slot"));
 
 		/*
-		 * Do not allow users to enable failover for slots that enable
-		 * two-phase decoding.
+		 * Do not allow users to enable both failover and two_phase for slots.
 		 *
 		 * This is because the two_phase_at field of a slot, which tracks the
-		 * LSN from which two-phase decoding starts, is not synchronized to
-		 * standby servers. Without this field, the logical decoding might
+		 * LSN, from which two-phase decoding starts, is not synchronized to
+		 * standby servers. Without two_phase_at, the logical decoding might
 		 * incorrectly identify prepared transaction as already replicated to
-		 * the subscriber, causing them to be skipped.
+		 * the subscriber after promotion of standby server, causing them to be
+		 * skipped.
 		 */
 		if (two_phase)
 			ereport(ERROR,
@@ -865,11 +865,10 @@ ReplicationSlotAlter(const char *name, bool failover)
 				errmsg("cannot enable failover for a temporary replication slot"));
 
 	/*
-	 * Do not allow users to enable failover for slots that enable two-phase
-	 * decoding.
+	 * Do not allow users to enable failover for a two_phase enabled slot.
 	 *
-	 * See comments atop the similar check in ReplicationSlotCreate() for
-	 * detailed reasons.
+	 * See comments atop the similar check in ReplicationSlotCreate() for a
+	 * detailed reason.
 	 */
 	if (failover && MyReplicationSlot->data.two_phase)
 		ereport(ERROR,


Attachments:

  [text/plain] v3-0002-amit.1.patch.txt (3.1K, ../../CAA4eK1JbLBeZfm7LHjsMipgTDrrzfmfxJKmurJqPkpfCQ9E41A@mail.gmail.com/2-v3-0002-amit.1.patch.txt)
  download | inline diff:
diff --git a/src/backend/commands/subscriptioncmds.c b/src/backend/commands/subscriptioncmds.c
index 6db3c9347fa..09c5f0ef685 100644
--- a/src/backend/commands/subscriptioncmds.c
+++ b/src/backend/commands/subscriptioncmds.c
@@ -649,10 +649,11 @@ CreateSubscription(ParseState *pstate, CreateSubscriptionStmt *stmt,
 				 errhint("Subscriptions with the password_required option set to false may only be created or modified by the superuser.")));
 
 	/*
-	 * Do not allow users to enable failover and two_phase option together.
+	 * Do not allow users to enable the failover and two_phase options
+	 * together.
 	 *
-	 * See comments atop the similar check in ReplicationSlotCreate() for
-	 * detailed reasons.
+	 * See comments atop the similar check in ReplicationSlotCreate() for a
+	 * detailed reason.
 	 */
 	if (opts.twophase && opts.failover)
 		ereport(ERROR,
@@ -1258,11 +1259,11 @@ AlterSubscription(ParseState *pstate, AlterSubscriptionStmt *stmt,
 										"failover")));
 
 					/*
-					 * Do not allow users to enable failover and two_phase
-					 * option together.
+					 * Do not allow users to enable the failover and two_phase
+					 * options together.
 					 *
 					 * See comments atop the similar check in
-					 * ReplicationSlotCreate() for detailed reasons.
+					 * ReplicationSlotCreate() for a detailed reason.
 					 */
 					if (sub->twophasestate != LOGICALREP_TWOPHASE_STATE_DISABLED &&
 						opts.failover)
diff --git a/src/backend/replication/slot.c b/src/backend/replication/slot.c
index f40028bd941..d251ce95fe6 100644
--- a/src/backend/replication/slot.c
+++ b/src/backend/replication/slot.c
@@ -345,14 +345,14 @@ ReplicationSlotCreate(const char *name, bool db_specific,
 					errmsg("cannot enable failover for a temporary replication slot"));
 
 		/*
-		 * Do not allow users to enable failover for slots that enable
-		 * two-phase decoding.
+		 * Do not allow users to enable both failover and two_phase for slots.
 		 *
 		 * This is because the two_phase_at field of a slot, which tracks the
-		 * LSN from which two-phase decoding starts, is not synchronized to
-		 * standby servers. Without this field, the logical decoding might
+		 * LSN, from which two-phase decoding starts, is not synchronized to
+		 * standby servers. Without two_phase_at, the logical decoding might
 		 * incorrectly identify prepared transaction as already replicated to
-		 * the subscriber, causing them to be skipped.
+		 * the subscriber after promotion of standby server, causing them to be
+		 * skipped.
 		 */
 		if (two_phase)
 			ereport(ERROR,
@@ -865,11 +865,10 @@ ReplicationSlotAlter(const char *name, bool failover)
 				errmsg("cannot enable failover for a temporary replication slot"));
 
 	/*
-	 * Do not allow users to enable failover for slots that enable two-phase
-	 * decoding.
+	 * Do not allow users to enable failover for a two_phase enabled slot.
 	 *
-	 * See comments atop the similar check in ReplicationSlotCreate() for
-	 * detailed reasons.
+	 * See comments atop the similar check in ReplicationSlotCreate() for a
+	 * detailed reason.
 	 */
 	if (failover && MyReplicationSlot->data.two_phase)
 		ereport(ERROR,


^ permalink  raw  reply  [nested|flat] 88+ messages in thread

* RE: Fix slot synchronization with two_phase decoding enabled
@ 2025-04-02 05:55  Zhijie Hou (Fujitsu) <[email protected]>
  parent: Amit Kapila <[email protected]>
  0 siblings, 0 replies; 88+ messages in thread

From: Zhijie Hou (Fujitsu) @ 2025-04-02 05:55 UTC (permalink / raw)
  To: Amit Kapila <[email protected]>; +Cc: PostgreSQL Hackers <[email protected]>; Hayato Kuroda (Fujitsu) <[email protected]>

On Wed, Apr 2, 2025 at 12:41 PM Amit Kapila wrote:

> 
> On Tue, Apr 1, 2025 at 4:28 PM Zhijie Hou (Fujitsu) 
> <[email protected]>
> wrote:
> >
> > Here is the V3 patch set which addressed all the comments.
> >
> 
> Comment 0n 0001
> <literal>NULL</literal> for logical slots where
> +       <structfield>two_phase</structfield> is false and physical slots.
> +      </para></entry>
> 
> change above to:
> <literal>NULL</literal> for logical slots where 
> <structfield>two_phase</structfield> is false and for physical slots.

Changed.

> 
> Comment on 0002
> +# Create a subscription with two_phase enabled 
> +$subscriber1->safe_psql('postgres',
> + "CREATE SUBSCRIPTION regress_mysub2 CONNECTION
> '$publisher_connstr'
> PUBLICATION regress_mypub WITH (slot_name = lsub1_slot, create_slot = 
> false, enabled = false, two_phase = true);"
> +);
> +
> +# Enable failover for the subscription ($result, $stdout, $stderr) = 
> +$subscriber1->psql('postgres',  "ALTER SUBSCRIPTION regress_mysub2 
> +SET (failover = true)"); ok( $stderr =~
> +/ERROR:  cannot enable failover for a two_phase
> enabled subscription/,
> + "Enabling failover is not allowed for a two_phase enabled 
> + subscription");
> 
> Is there a need for this test to be in .pl file? Can't we add it in .sql file?

Right, I moved the test into subscription.sql

> Apart from the above, I have made minor modifications to the PG17 
> patch in the attached.

Here is V4 patch set which addressed above comments and passed
pgindent test.

Best Regards,
Hou zj

From e1ad472436f02ed9b410bc96c1b5d0e7952f7883 Mon Sep 17 00:00:00 2001
From: Hou Zhijie <[email protected]>
Date: Mon, 31 Mar 2025 16:28:57 +0800
Subject: [PATCH v4 2/2] Fix slot synchronization for two_phase enables slots.

The issue is that the transactions prepared before two-phase decoding is
enabled can fail to replicate to the subscriber after being committed on a
promoted standby following a failover. This is because the two_phase_at
field of a slot, which tracks the LSN from which two-phase decoding
starts, is not synchronized to standby servers. Without two_phase_at, the
logical decoding might incorrectly identify prepared transaction as
already replicated to the subscriber after promotion of standby server,
causing them to be skipped.

To address the issue on HEAD, the two_phase_at field of the slot is
exposed by the pg_replication_slots view and allows the slot
synchronization to copy this value to the corresponding synced slot on the
standby server.

However, we can't fix the issue in the same way in PG17 where slot
synchronization has been introduced, as it requires a change in view and
builtin function definition, which in turn requires a catversion bump.
Instead, to prevent the risk of losing prepared transactions, we disallow
enabling failover and two-phase decoding together for a replication slot.
Users are advised to disable slot synchronization for two_phase-enabled
slots or re-create the subscriptions with option 'two_phase' as false and
'failover' as true.
---
 contrib/test_decoding/expected/slot.out    |  2 ++
 contrib/test_decoding/sql/slot.sql         |  1 +
 src/backend/commands/subscriptioncmds.c    | 26 +++++++++++++++++++++
 src/backend/replication/slot.c             | 27 ++++++++++++++++++++++
 src/bin/pg_upgrade/t/003_logical_slots.pl  |  6 ++---
 src/test/regress/expected/subscription.out |  6 +++++
 src/test/regress/sql/subscription.sql      |  7 ++++++
 7 files changed, 72 insertions(+), 3 deletions(-)

diff --git a/contrib/test_decoding/expected/slot.out b/contrib/test_decoding/expected/slot.out
index 7de03c79f6f..8fd762dea85 100644
--- a/contrib/test_decoding/expected/slot.out
+++ b/contrib/test_decoding/expected/slot.out
@@ -427,6 +427,8 @@ SELECT 'init' FROM pg_create_logical_replication_slot('failover_default_slot', '
 
 SELECT 'init' FROM pg_create_logical_replication_slot('failover_true_temp_slot', 'test_decoding', true, false, true);
 ERROR:  cannot enable failover for a temporary replication slot
+SELECT 'init' FROM pg_create_logical_replication_slot('failover_twophase_true_slot', 'test_decoding', false, true, true);
+ERROR:  "failover" and "two_phase" are mutually exclusive options
 SELECT 'init' FROM pg_create_physical_replication_slot('physical_slot');
  ?column? 
 ----------
diff --git a/contrib/test_decoding/sql/slot.sql b/contrib/test_decoding/sql/slot.sql
index 580e3ae3bef..a89fe712ff6 100644
--- a/contrib/test_decoding/sql/slot.sql
+++ b/contrib/test_decoding/sql/slot.sql
@@ -182,6 +182,7 @@ SELECT 'init' FROM pg_create_logical_replication_slot('failover_true_slot', 'tes
 SELECT 'init' FROM pg_create_logical_replication_slot('failover_false_slot', 'test_decoding', false, false, false);
 SELECT 'init' FROM pg_create_logical_replication_slot('failover_default_slot', 'test_decoding', false, false);
 SELECT 'init' FROM pg_create_logical_replication_slot('failover_true_temp_slot', 'test_decoding', true, false, true);
+SELECT 'init' FROM pg_create_logical_replication_slot('failover_twophase_true_slot', 'test_decoding', false, true, true);
 SELECT 'init' FROM pg_create_physical_replication_slot('physical_slot');
 
 SELECT slot_name, slot_type, failover FROM pg_replication_slots;
diff --git a/src/backend/commands/subscriptioncmds.c b/src/backend/commands/subscriptioncmds.c
index 9467f58a23d..09c5f0ef685 100644
--- a/src/backend/commands/subscriptioncmds.c
+++ b/src/backend/commands/subscriptioncmds.c
@@ -648,6 +648,19 @@ CreateSubscription(ParseState *pstate, CreateSubscriptionStmt *stmt,
 				 errmsg("password_required=false is superuser-only"),
 				 errhint("Subscriptions with the password_required option set to false may only be created or modified by the superuser.")));
 
+	/*
+	 * Do not allow users to enable the failover and two_phase options
+	 * together.
+	 *
+	 * See comments atop the similar check in ReplicationSlotCreate() for a
+	 * detailed reason.
+	 */
+	if (opts.twophase && opts.failover)
+		ereport(ERROR,
+				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				errmsg("\"%s\" and \"%s\" are mutually exclusive options",
+					   "failover", "two_phase"));
+
 	/*
 	 * If built with appropriate switch, whine when regression-testing
 	 * conventions for subscription names are violated.
@@ -1245,6 +1258,19 @@ AlterSubscription(ParseState *pstate, AlterSubscriptionStmt *stmt,
 								 errmsg("cannot set %s for enabled subscription",
 										"failover")));
 
+					/*
+					 * Do not allow users to enable the failover and two_phase
+					 * options together.
+					 *
+					 * See comments atop the similar check in
+					 * ReplicationSlotCreate() for a detailed reason.
+					 */
+					if (sub->twophasestate != LOGICALREP_TWOPHASE_STATE_DISABLED &&
+						opts.failover)
+						ereport(ERROR,
+								errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+								errmsg("cannot enable failover for a two_phase enabled subscription"));
+
 					/*
 					 * The changed failover option of the slot can't be rolled
 					 * back.
diff --git a/src/backend/replication/slot.c b/src/backend/replication/slot.c
index 780d22afbca..3293651f725 100644
--- a/src/backend/replication/slot.c
+++ b/src/backend/replication/slot.c
@@ -343,6 +343,22 @@ ReplicationSlotCreate(const char *name, bool db_specific,
 			ereport(ERROR,
 					errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 					errmsg("cannot enable failover for a temporary replication slot"));
+
+		/*
+		 * Do not allow users to enable both failover and two_phase for slots.
+		 *
+		 * This is because the two_phase_at field of a slot, which tracks the
+		 * LSN, from which two-phase decoding starts, is not synchronized to
+		 * standby servers. Without two_phase_at, the logical decoding might
+		 * incorrectly identify prepared transaction as already replicated to
+		 * the subscriber after promotion of standby server, causing them to
+		 * be skipped.
+		 */
+		if (two_phase)
+			ereport(ERROR,
+					errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+					errmsg("\"%s\" and \"%s\" are mutually exclusive options",
+						   "failover", "two_phase"));
 	}
 
 	/*
@@ -848,6 +864,17 @@ ReplicationSlotAlter(const char *name, bool failover)
 				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				errmsg("cannot enable failover for a temporary replication slot"));
 
+	/*
+	 * Do not allow users to enable failover for a two_phase enabled slot.
+	 *
+	 * See comments atop the similar check in ReplicationSlotCreate() for a
+	 * detailed reason.
+	 */
+	if (failover && MyReplicationSlot->data.two_phase)
+		ereport(ERROR,
+				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				errmsg("cannot enable failover for a two-phase enabled replication slot"));
+
 	if (MyReplicationSlot->data.failover != failover)
 	{
 		SpinLockAcquire(&MyReplicationSlot->mutex);
diff --git a/src/bin/pg_upgrade/t/003_logical_slots.pl b/src/bin/pg_upgrade/t/003_logical_slots.pl
index 0a2483d3dfc..e329cc609ce 100644
--- a/src/bin/pg_upgrade/t/003_logical_slots.pl
+++ b/src/bin/pg_upgrade/t/003_logical_slots.pl
@@ -173,7 +173,7 @@ $sub->start;
 $sub->safe_psql(
 	'postgres', qq[
 	CREATE TABLE tbl (a int);
-	CREATE SUBSCRIPTION regress_sub CONNECTION '$old_connstr' PUBLICATION regress_pub WITH (two_phase = 'true', failover = 'true')
+	CREATE SUBSCRIPTION regress_sub CONNECTION '$old_connstr' PUBLICATION regress_pub WITH (two_phase = 'true')
 ]);
 $sub->wait_for_subscription_sync($oldpub, 'regress_sub');
 
@@ -193,8 +193,8 @@ command_ok([@pg_upgrade_cmd], 'run of pg_upgrade of old cluster');
 # Check that the slot 'regress_sub' has migrated to the new cluster
 $newpub->start;
 my $result = $newpub->safe_psql('postgres',
-	"SELECT slot_name, two_phase, failover FROM pg_replication_slots");
-is($result, qq(regress_sub|t|t), 'check the slot exists on new cluster');
+	"SELECT slot_name, two_phase FROM pg_replication_slots");
+is($result, qq(regress_sub|t), 'check the slot exists on new cluster');
 
 # Update the connection
 my $new_connstr = $newpub->connstr . ' dbname=postgres';
diff --git a/src/test/regress/expected/subscription.out b/src/test/regress/expected/subscription.out
index 0f2a25cdc19..fd94389d916 100644
--- a/src/test/regress/expected/subscription.out
+++ b/src/test/regress/expected/subscription.out
@@ -389,6 +389,9 @@ ALTER SUBSCRIPTION regress_testsub SET (streaming = true);
  regress_testsub | regress_subscription_user | f       | {testpub}   | f      | on        | p                | f                | any    | t                 | f             | f        | off                | dbname=regress_doesnotexist | 0/0
 (1 row)
 
+--fail - cannot enable failover for a two_phase enabled subscription
+ALTER SUBSCRIPTION regress_testsub SET (failover = true);
+ERROR:  cannot enable failover for a two_phase enabled subscription
 ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
 DROP SUBSCRIPTION regress_testsub;
 -- two_phase and streaming are compatible.
@@ -479,6 +482,9 @@ COMMIT;
 ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
 DROP SUBSCRIPTION regress_testsub;
 RESET SESSION AUTHORIZATION;
+-- fail - cannot enable two_phase and failover together
+CREATE SUBSCRIPTION regress_testsub CONNECTION 'dbname=regress_doesnotexist' PUBLICATION testpub WITH (connect = false, two_phase = true, failover = true);
+ERROR:  "failover" and "two_phase" are mutually exclusive options
 DROP ROLE regress_subscription_user;
 DROP ROLE regress_subscription_user2;
 DROP ROLE regress_subscription_user3;
diff --git a/src/test/regress/sql/subscription.sql b/src/test/regress/sql/subscription.sql
index 3e5ba4cb8c6..bc6e0f04e64 100644
--- a/src/test/regress/sql/subscription.sql
+++ b/src/test/regress/sql/subscription.sql
@@ -264,6 +264,9 @@ ALTER SUBSCRIPTION regress_testsub SET (streaming = true);
 
 \dRs+
 
+--fail - cannot enable failover for a two_phase enabled subscription
+ALTER SUBSCRIPTION regress_testsub SET (failover = true);
+
 ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
 DROP SUBSCRIPTION regress_testsub;
 
@@ -342,6 +345,10 @@ ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
 DROP SUBSCRIPTION regress_testsub;
 
 RESET SESSION AUTHORIZATION;
+
+-- fail - cannot enable two_phase and failover together
+CREATE SUBSCRIPTION regress_testsub CONNECTION 'dbname=regress_doesnotexist' PUBLICATION testpub WITH (connect = false, two_phase = true, failover = true);
+
 DROP ROLE regress_subscription_user;
 DROP ROLE regress_subscription_user2;
 DROP ROLE regress_subscription_user3;
-- 
2.31.1



Attachments:

  [application/octet-stream] v4-0001-HEAD-Fix-slot-synchronization-for-two_phase-enables-sl.patch (14.3K, ../../OS3PR01MB571870D041C9E0E555A4FC6094AF2@OS3PR01MB5718.jpnprd01.prod.outlook.com/2-v4-0001-HEAD-Fix-slot-synchronization-for-two_phase-enables-sl.patch)
  download | inline diff:
From 470ef78dc9b0c2a9eabdc29b976651f34b76a277 Mon Sep 17 00:00:00 2001
From: Hou Zhijie <[email protected]>
Date: Thu, 27 Feb 2025 10:49:32 +0800
Subject: [PATCH v4] Fix slot synchronization for two_phase enables slots.

The issue is that the transactions prepared before two-phase decoding is
enabled can fail to replicate to the subscriber after being committed on a
promoted standby following a failover. This is because the two_phase_at
field of a slot, which tracks the LSN from which two-phase decoding
starts, is not synchronized to standby servers. Without two_phase_at, the
logical decoding might incorrectly identify prepared transaction as
already replicated to the subscriber after promotion of standby server,
causing them to be skipped.

To address the issue on HEAD, the two_phase_at field of the slot is
exposed by the pg_replication_slots view and allows the slot
synchronization to copy this value to the corresponding synced slot on the
standby server.

However, we can't fix the issue in the same way in PG17 where slot
synchronization has been introduced, as it requires a change in view and
builtin function definition, which in turn requires a catversion bump.
Instead, to prevent the risk of losing prepared transactions, we disallow
enabling failover and two-phase decoding together for a replication slot.
Users are advised to disable slot synchronization for two_phase-enabled
slots or re-create the subscriptions with option 'two_phase' as false and
'failover' as true.
---
 doc/src/sgml/system-views.sgml                | 11 +++
 src/backend/catalog/system_views.sql          |  1 +
 src/backend/replication/logical/slotsync.c    | 14 +++-
 src/backend/replication/slotfuncs.c           |  8 +-
 src/include/catalog/pg_proc.dat               |  6 +-
 .../t/040_standby_failover_slots_sync.pl      | 81 ++++++++++++++++++-
 src/test/regress/expected/rules.out           |  3 +-
 7 files changed, 111 insertions(+), 13 deletions(-)

diff --git a/doc/src/sgml/system-views.sgml b/doc/src/sgml/system-views.sgml
index e9a59af8c34..4f336ee0adf 100644
--- a/doc/src/sgml/system-views.sgml
+++ b/doc/src/sgml/system-views.sgml
@@ -2854,6 +2854,17 @@ SELECT * FROM pg_locks pl LEFT JOIN pg_prepared_xacts ppx
       </para></entry>
      </row>
 
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>two_phase_at</structfield> <type>pg_lsn</type>
+      </para>
+      <para>
+       The address (<literal>LSN</literal>) from which the decoding of prepared
+       transactions is enabled. <literal>NULL</literal> for logical slots
+       where <structfield>two_phase</structfield> is false and for physical slots.
+      </para></entry>
+     </row>
+
      <row>
       <entry role="catalog_table_entry"><para role="column_definition">
        <structfield>inactive_since</structfield> <type>timestamptz</type>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 64a7240aa77..273008db37f 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -1025,6 +1025,7 @@ CREATE VIEW pg_replication_slots AS
             L.wal_status,
             L.safe_wal_size,
             L.two_phase,
+            L.two_phase_at,
             L.inactive_since,
             L.conflicting,
             L.invalidation_reason,
diff --git a/src/backend/replication/logical/slotsync.c b/src/backend/replication/logical/slotsync.c
index 2c0a7439be4..e22d41891e6 100644
--- a/src/backend/replication/logical/slotsync.c
+++ b/src/backend/replication/logical/slotsync.c
@@ -139,6 +139,7 @@ typedef struct RemoteSlot
 	bool		failover;
 	XLogRecPtr	restart_lsn;
 	XLogRecPtr	confirmed_lsn;
+	XLogRecPtr	two_phase_at;
 	TransactionId catalog_xmin;
 
 	/* RS_INVAL_NONE if valid, or the reason of invalidation */
@@ -276,7 +277,8 @@ update_local_synced_slot(RemoteSlot *remote_slot, Oid remote_dbid,
 	if (remote_dbid != slot->data.database ||
 		remote_slot->two_phase != slot->data.two_phase ||
 		remote_slot->failover != slot->data.failover ||
-		strcmp(remote_slot->plugin, NameStr(slot->data.plugin)) != 0)
+		strcmp(remote_slot->plugin, NameStr(slot->data.plugin)) != 0 ||
+		remote_slot->two_phase_at != slot->data.two_phase_at)
 	{
 		NameData	plugin_name;
 
@@ -287,6 +289,7 @@ update_local_synced_slot(RemoteSlot *remote_slot, Oid remote_dbid,
 		slot->data.plugin = plugin_name;
 		slot->data.database = remote_dbid;
 		slot->data.two_phase = remote_slot->two_phase;
+		slot->data.two_phase_at = remote_slot->two_phase_at;
 		slot->data.failover = remote_slot->failover;
 		SpinLockRelease(&slot->mutex);
 
@@ -788,9 +791,9 @@ synchronize_one_slot(RemoteSlot *remote_slot, Oid remote_dbid)
 static bool
 synchronize_slots(WalReceiverConn *wrconn)
 {
-#define SLOTSYNC_COLUMN_COUNT 9
+#define SLOTSYNC_COLUMN_COUNT 10
 	Oid			slotRow[SLOTSYNC_COLUMN_COUNT] = {TEXTOID, TEXTOID, LSNOID,
-	LSNOID, XIDOID, BOOLOID, BOOLOID, TEXTOID, TEXTOID};
+	LSNOID, XIDOID, BOOLOID, LSNOID, BOOLOID, TEXTOID, TEXTOID};
 
 	WalRcvExecResult *res;
 	TupleTableSlot *tupslot;
@@ -798,7 +801,7 @@ synchronize_slots(WalReceiverConn *wrconn)
 	bool		some_slot_updated = false;
 	bool		started_tx = false;
 	const char *query = "SELECT slot_name, plugin, confirmed_flush_lsn,"
-		" restart_lsn, catalog_xmin, two_phase, failover,"
+		" restart_lsn, catalog_xmin, two_phase, two_phase_at, failover,"
 		" database, invalidation_reason"
 		" FROM pg_catalog.pg_replication_slots"
 		" WHERE failover and NOT temporary";
@@ -853,6 +856,9 @@ synchronize_slots(WalReceiverConn *wrconn)
 														   &isnull));
 		Assert(!isnull);
 
+		d = slot_getattr(tupslot, ++col, &isnull);
+		remote_slot->two_phase_at = isnull ? InvalidXLogRecPtr : DatumGetLSN(d);
+
 		remote_slot->failover = DatumGetBool(slot_getattr(tupslot, ++col,
 														  &isnull));
 		Assert(!isnull);
diff --git a/src/backend/replication/slotfuncs.c b/src/backend/replication/slotfuncs.c
index 146eef5871e..8a314b5ff3b 100644
--- a/src/backend/replication/slotfuncs.c
+++ b/src/backend/replication/slotfuncs.c
@@ -235,7 +235,7 @@ pg_drop_replication_slot(PG_FUNCTION_ARGS)
 Datum
 pg_get_replication_slots(PG_FUNCTION_ARGS)
 {
-#define PG_GET_REPLICATION_SLOTS_COLS 19
+#define PG_GET_REPLICATION_SLOTS_COLS 20
 	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
 	XLogRecPtr	currlsn;
 	int			slotno;
@@ -406,6 +406,12 @@ pg_get_replication_slots(PG_FUNCTION_ARGS)
 
 		values[i++] = BoolGetDatum(slot_contents.data.two_phase);
 
+		if (slot_contents.data.two_phase &&
+			!XLogRecPtrIsInvalid(slot_contents.data.two_phase_at))
+			values[i++] = LSNGetDatum(slot_contents.data.two_phase_at);
+		else
+			nulls[i++] = true;
+
 		if (slot_contents.inactive_since > 0)
 			values[i++] = TimestampTzGetDatum(slot_contents.inactive_since);
 		else
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 6b57b7e18d9..30e77458b5d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -11421,9 +11421,9 @@
   proname => 'pg_get_replication_slots', prorows => '10', proisstrict => 'f',
   proretset => 't', provolatile => 's', prorettype => 'record',
   proargtypes => '',
-  proallargtypes => '{name,name,text,oid,bool,bool,int4,xid,xid,pg_lsn,pg_lsn,text,int8,bool,timestamptz,bool,text,bool,bool}',
-  proargmodes => '{o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
-  proargnames => '{slot_name,plugin,slot_type,datoid,temporary,active,active_pid,xmin,catalog_xmin,restart_lsn,confirmed_flush_lsn,wal_status,safe_wal_size,two_phase,inactive_since,conflicting,invalidation_reason,failover,synced}',
+  proallargtypes => '{name,name,text,oid,bool,bool,int4,xid,xid,pg_lsn,pg_lsn,text,int8,bool,pg_lsn,timestamptz,bool,text,bool,bool}',
+  proargmodes => '{o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{slot_name,plugin,slot_type,datoid,temporary,active,active_pid,xmin,catalog_xmin,restart_lsn,confirmed_flush_lsn,wal_status,safe_wal_size,two_phase,two_phase_at,inactive_since,conflicting,invalidation_reason,failover,synced}',
   prosrc => 'pg_get_replication_slots' },
 { oid => '3786', descr => 'set up a logical replication slot',
   proname => 'pg_create_logical_replication_slot', provolatile => 'v',
diff --git a/src/test/recovery/t/040_standby_failover_slots_sync.pl b/src/test/recovery/t/040_standby_failover_slots_sync.pl
index 8f65142909a..9c8b49e942d 100644
--- a/src/test/recovery/t/040_standby_failover_slots_sync.pl
+++ b/src/test/recovery/t/040_standby_failover_slots_sync.pl
@@ -22,7 +22,11 @@ $publisher->init(
 # Disable autovacuum to avoid generating xid during stats update as otherwise
 # the new XID could then be replicated to standby at some random point making
 # slots at primary lag behind standby during slot sync.
-$publisher->append_conf('postgresql.conf', 'autovacuum = off');
+$publisher->append_conf(
+	'postgresql.conf', qq{
+autovacuum = off
+max_prepared_transactions = 1
+});
 $publisher->start;
 
 $publisher->safe_psql('postgres',
@@ -33,6 +37,7 @@ my $publisher_connstr = $publisher->connstr . ' dbname=postgres';
 # Create a subscriber node, wait for sync to complete
 my $subscriber1 = PostgreSQL::Test::Cluster->new('subscriber1');
 $subscriber1->init;
+$subscriber1->append_conf('postgresql.conf', 'max_prepared_transactions = 1');
 $subscriber1->start;
 
 # Capture the time before the logical failover slot is created on the
@@ -830,13 +835,72 @@ $primary->adjust_conf('postgresql.conf', 'synchronized_standby_slots',
 	"'sb1_slot'");
 $primary->reload;
 
+##################################################
+# Test the synchronization of the two_phase setting for a subscription with the
+# standby. Additionally, prepare a transaction before enabling the two_phase
+# option; subsequent tests will verify if it can be correctly replicated to the
+# subscriber after committing it on the promoted standby.
+##################################################
+
+$standby1->start;
+
+# Prepare a transaction
+$primary->safe_psql(
+	'postgres', qq[
+	BEGIN;
+	INSERT INTO tab_int values(0);
+	PREPARE TRANSACTION 'test_twophase_slotsync';
+]);
+
+$primary->wait_for_replay_catchup($standby1);
+$primary->wait_for_catchup('regress_mysub1');
+
+# Disable the subscription to allow changing the two_phase option.
+$subscriber1->safe_psql('postgres',
+	"ALTER SUBSCRIPTION regress_mysub1 DISABLE");
+
+# Wait for the replication slot to become inactive on the publisher
+$primary->poll_query_until(
+	'postgres',
+	"SELECT COUNT(*) FROM pg_catalog.pg_replication_slots WHERE slot_name = 'lsub1_slot' AND active='f'",
+	1);
+
+# Set two_phase to true and enable the subscription
+$subscriber1->safe_psql(
+	'postgres', qq[
+	ALTER SUBSCRIPTION regress_mysub1 SET (two_phase = true);
+	ALTER SUBSCRIPTION regress_mysub1 ENABLE;
+]);
+
+$primary->wait_for_catchup('regress_mysub1');
+
+my $two_phase_at = $primary->safe_psql('postgres',
+	"SELECT two_phase_at from pg_replication_slots WHERE slot_name = 'lsub1_slot';"
+);
+
+# Confirm that two_phase setting of lsub1_slot slot is synced to the standby
+ok( $standby1->poll_query_until(
+		'postgres',
+		"SELECT two_phase AND '$two_phase_at' = two_phase_at from pg_replication_slots WHERE slot_name = 'lsub1_slot' AND synced AND NOT temporary;"
+	),
+	'two_phase setting of slot lsub1_slot synced to standby');
+
+# Confirm that the prepared transaction is not yet replicated to the
+# subscriber.
+$result = $subscriber1->safe_psql('postgres',
+	"SELECT count(*) = 0 FROM pg_prepared_xacts;");
+is($result, 't',
+	"the prepared transaction is not replicated to the subscriber");
+
 ##################################################
 # Promote the standby1 to primary. Confirm that:
 # a) the slot 'lsub1_slot' and 'snap_test_slot' are retained on the new primary
 # b) logical replication for regress_mysub1 is resumed successfully after failover
-# c) changes can be consumed from the synced slot 'snap_test_slot'
+# c) changes from the transaction prepared 'test_twophase_slotsync' can be
+#    consumed from the synced slot 'snap_test_slot' once committed on the new
+#    primary.
+# d) changes can be consumed from the synced slot 'snap_test_slot'
 ##################################################
-$standby1->start;
 $primary->wait_for_replay_catchup($standby1);
 
 # Capture the time before the standby is promoted
@@ -876,6 +940,15 @@ is( $standby1->safe_psql(
 	't',
 	'synced slot retained on the new primary');
 
+# Commit the prepared transaction
+$standby1->safe_psql('postgres',
+	"COMMIT PREPARED 'test_twophase_slotsync';");
+$standby1->wait_for_catchup('regress_mysub1');
+
+# Confirm that the prepared transaction is replicated to the subscriber
+is($subscriber1->safe_psql('postgres', q{SELECT count(*) FROM tab_int;}),
+	"11", 'prepared data replicated from the new primary');
+
 # Insert data on the new primary
 $standby1->safe_psql('postgres',
 	"INSERT INTO tab_int SELECT generate_series(11, 20);");
@@ -883,7 +956,7 @@ $standby1->wait_for_catchup('regress_mysub1');
 
 # Confirm that data in tab_int replicated on the subscriber
 is($subscriber1->safe_psql('postgres', q{SELECT count(*) FROM tab_int;}),
-	"20", 'data replicated from the new primary');
+	"21", 'data replicated from the new primary');
 
 # Consume the data from the snap_test_slot. The synced slot should reach a
 # consistent point by restoring the snapshot at the restart_lsn serialized
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index d9533deb04e..673c63b8d1b 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1490,12 +1490,13 @@ pg_replication_slots| SELECT l.slot_name,
     l.wal_status,
     l.safe_wal_size,
     l.two_phase,
+    l.two_phase_at,
     l.inactive_since,
     l.conflicting,
     l.invalidation_reason,
     l.failover,
     l.synced
-   FROM (pg_get_replication_slots() l(slot_name, plugin, slot_type, datoid, temporary, active, active_pid, xmin, catalog_xmin, restart_lsn, confirmed_flush_lsn, wal_status, safe_wal_size, two_phase, inactive_since, conflicting, invalidation_reason, failover, synced)
+   FROM (pg_get_replication_slots() l(slot_name, plugin, slot_type, datoid, temporary, active, active_pid, xmin, catalog_xmin, restart_lsn, confirmed_flush_lsn, wal_status, safe_wal_size, two_phase, two_phase_at, inactive_since, conflicting, invalidation_reason, failover, synced)
      LEFT JOIN pg_database d ON ((l.datoid = d.oid)));
 pg_roles| SELECT pg_authid.rolname,
     pg_authid.rolsuper,
-- 
2.30.0.windows.2



  [text/plain] v4-0002-PG17-Fix-slot-synchronization-for-two_phase-enables-sl.patch.txt (10.7K, ../../OS3PR01MB571870D041C9E0E555A4FC6094AF2@OS3PR01MB5718.jpnprd01.prod.outlook.com/3-v4-0002-PG17-Fix-slot-synchronization-for-two_phase-enables-sl.patch.txt)
  download | inline diff:
From e1ad472436f02ed9b410bc96c1b5d0e7952f7883 Mon Sep 17 00:00:00 2001
From: Hou Zhijie <[email protected]>
Date: Mon, 31 Mar 2025 16:28:57 +0800
Subject: [PATCH v4 2/2] Fix slot synchronization for two_phase enables slots.

The issue is that the transactions prepared before two-phase decoding is
enabled can fail to replicate to the subscriber after being committed on a
promoted standby following a failover. This is because the two_phase_at
field of a slot, which tracks the LSN from which two-phase decoding
starts, is not synchronized to standby servers. Without two_phase_at, the
logical decoding might incorrectly identify prepared transaction as
already replicated to the subscriber after promotion of standby server,
causing them to be skipped.

To address the issue on HEAD, the two_phase_at field of the slot is
exposed by the pg_replication_slots view and allows the slot
synchronization to copy this value to the corresponding synced slot on the
standby server.

However, we can't fix the issue in the same way in PG17 where slot
synchronization has been introduced, as it requires a change in view and
builtin function definition, which in turn requires a catversion bump.
Instead, to prevent the risk of losing prepared transactions, we disallow
enabling failover and two-phase decoding together for a replication slot.
Users are advised to disable slot synchronization for two_phase-enabled
slots or re-create the subscriptions with option 'two_phase' as false and
'failover' as true.
---
 contrib/test_decoding/expected/slot.out    |  2 ++
 contrib/test_decoding/sql/slot.sql         |  1 +
 src/backend/commands/subscriptioncmds.c    | 26 +++++++++++++++++++++
 src/backend/replication/slot.c             | 27 ++++++++++++++++++++++
 src/bin/pg_upgrade/t/003_logical_slots.pl  |  6 ++---
 src/test/regress/expected/subscription.out |  6 +++++
 src/test/regress/sql/subscription.sql      |  7 ++++++
 7 files changed, 72 insertions(+), 3 deletions(-)

diff --git a/contrib/test_decoding/expected/slot.out b/contrib/test_decoding/expected/slot.out
index 7de03c79f6f..8fd762dea85 100644
--- a/contrib/test_decoding/expected/slot.out
+++ b/contrib/test_decoding/expected/slot.out
@@ -427,6 +427,8 @@ SELECT 'init' FROM pg_create_logical_replication_slot('failover_default_slot', '
 
 SELECT 'init' FROM pg_create_logical_replication_slot('failover_true_temp_slot', 'test_decoding', true, false, true);
 ERROR:  cannot enable failover for a temporary replication slot
+SELECT 'init' FROM pg_create_logical_replication_slot('failover_twophase_true_slot', 'test_decoding', false, true, true);
+ERROR:  "failover" and "two_phase" are mutually exclusive options
 SELECT 'init' FROM pg_create_physical_replication_slot('physical_slot');
  ?column? 
 ----------
diff --git a/contrib/test_decoding/sql/slot.sql b/contrib/test_decoding/sql/slot.sql
index 580e3ae3bef..a89fe712ff6 100644
--- a/contrib/test_decoding/sql/slot.sql
+++ b/contrib/test_decoding/sql/slot.sql
@@ -182,6 +182,7 @@ SELECT 'init' FROM pg_create_logical_replication_slot('failover_true_slot', 'tes
 SELECT 'init' FROM pg_create_logical_replication_slot('failover_false_slot', 'test_decoding', false, false, false);
 SELECT 'init' FROM pg_create_logical_replication_slot('failover_default_slot', 'test_decoding', false, false);
 SELECT 'init' FROM pg_create_logical_replication_slot('failover_true_temp_slot', 'test_decoding', true, false, true);
+SELECT 'init' FROM pg_create_logical_replication_slot('failover_twophase_true_slot', 'test_decoding', false, true, true);
 SELECT 'init' FROM pg_create_physical_replication_slot('physical_slot');
 
 SELECT slot_name, slot_type, failover FROM pg_replication_slots;
diff --git a/src/backend/commands/subscriptioncmds.c b/src/backend/commands/subscriptioncmds.c
index 9467f58a23d..09c5f0ef685 100644
--- a/src/backend/commands/subscriptioncmds.c
+++ b/src/backend/commands/subscriptioncmds.c
@@ -648,6 +648,19 @@ CreateSubscription(ParseState *pstate, CreateSubscriptionStmt *stmt,
 				 errmsg("password_required=false is superuser-only"),
 				 errhint("Subscriptions with the password_required option set to false may only be created or modified by the superuser.")));
 
+	/*
+	 * Do not allow users to enable the failover and two_phase options
+	 * together.
+	 *
+	 * See comments atop the similar check in ReplicationSlotCreate() for a
+	 * detailed reason.
+	 */
+	if (opts.twophase && opts.failover)
+		ereport(ERROR,
+				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				errmsg("\"%s\" and \"%s\" are mutually exclusive options",
+					   "failover", "two_phase"));
+
 	/*
 	 * If built with appropriate switch, whine when regression-testing
 	 * conventions for subscription names are violated.
@@ -1245,6 +1258,19 @@ AlterSubscription(ParseState *pstate, AlterSubscriptionStmt *stmt,
 								 errmsg("cannot set %s for enabled subscription",
 										"failover")));
 
+					/*
+					 * Do not allow users to enable the failover and two_phase
+					 * options together.
+					 *
+					 * See comments atop the similar check in
+					 * ReplicationSlotCreate() for a detailed reason.
+					 */
+					if (sub->twophasestate != LOGICALREP_TWOPHASE_STATE_DISABLED &&
+						opts.failover)
+						ereport(ERROR,
+								errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+								errmsg("cannot enable failover for a two_phase enabled subscription"));
+
 					/*
 					 * The changed failover option of the slot can't be rolled
 					 * back.
diff --git a/src/backend/replication/slot.c b/src/backend/replication/slot.c
index 780d22afbca..3293651f725 100644
--- a/src/backend/replication/slot.c
+++ b/src/backend/replication/slot.c
@@ -343,6 +343,22 @@ ReplicationSlotCreate(const char *name, bool db_specific,
 			ereport(ERROR,
 					errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 					errmsg("cannot enable failover for a temporary replication slot"));
+
+		/*
+		 * Do not allow users to enable both failover and two_phase for slots.
+		 *
+		 * This is because the two_phase_at field of a slot, which tracks the
+		 * LSN, from which two-phase decoding starts, is not synchronized to
+		 * standby servers. Without two_phase_at, the logical decoding might
+		 * incorrectly identify prepared transaction as already replicated to
+		 * the subscriber after promotion of standby server, causing them to
+		 * be skipped.
+		 */
+		if (two_phase)
+			ereport(ERROR,
+					errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+					errmsg("\"%s\" and \"%s\" are mutually exclusive options",
+						   "failover", "two_phase"));
 	}
 
 	/*
@@ -848,6 +864,17 @@ ReplicationSlotAlter(const char *name, bool failover)
 				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				errmsg("cannot enable failover for a temporary replication slot"));
 
+	/*
+	 * Do not allow users to enable failover for a two_phase enabled slot.
+	 *
+	 * See comments atop the similar check in ReplicationSlotCreate() for a
+	 * detailed reason.
+	 */
+	if (failover && MyReplicationSlot->data.two_phase)
+		ereport(ERROR,
+				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				errmsg("cannot enable failover for a two-phase enabled replication slot"));
+
 	if (MyReplicationSlot->data.failover != failover)
 	{
 		SpinLockAcquire(&MyReplicationSlot->mutex);
diff --git a/src/bin/pg_upgrade/t/003_logical_slots.pl b/src/bin/pg_upgrade/t/003_logical_slots.pl
index 0a2483d3dfc..e329cc609ce 100644
--- a/src/bin/pg_upgrade/t/003_logical_slots.pl
+++ b/src/bin/pg_upgrade/t/003_logical_slots.pl
@@ -173,7 +173,7 @@ $sub->start;
 $sub->safe_psql(
 	'postgres', qq[
 	CREATE TABLE tbl (a int);
-	CREATE SUBSCRIPTION regress_sub CONNECTION '$old_connstr' PUBLICATION regress_pub WITH (two_phase = 'true', failover = 'true')
+	CREATE SUBSCRIPTION regress_sub CONNECTION '$old_connstr' PUBLICATION regress_pub WITH (two_phase = 'true')
 ]);
 $sub->wait_for_subscription_sync($oldpub, 'regress_sub');
 
@@ -193,8 +193,8 @@ command_ok([@pg_upgrade_cmd], 'run of pg_upgrade of old cluster');
 # Check that the slot 'regress_sub' has migrated to the new cluster
 $newpub->start;
 my $result = $newpub->safe_psql('postgres',
-	"SELECT slot_name, two_phase, failover FROM pg_replication_slots");
-is($result, qq(regress_sub|t|t), 'check the slot exists on new cluster');
+	"SELECT slot_name, two_phase FROM pg_replication_slots");
+is($result, qq(regress_sub|t), 'check the slot exists on new cluster');
 
 # Update the connection
 my $new_connstr = $newpub->connstr . ' dbname=postgres';
diff --git a/src/test/regress/expected/subscription.out b/src/test/regress/expected/subscription.out
index 0f2a25cdc19..fd94389d916 100644
--- a/src/test/regress/expected/subscription.out
+++ b/src/test/regress/expected/subscription.out
@@ -389,6 +389,9 @@ ALTER SUBSCRIPTION regress_testsub SET (streaming = true);
  regress_testsub | regress_subscription_user | f       | {testpub}   | f      | on        | p                | f                | any    | t                 | f             | f        | off                | dbname=regress_doesnotexist | 0/0
 (1 row)
 
+--fail - cannot enable failover for a two_phase enabled subscription
+ALTER SUBSCRIPTION regress_testsub SET (failover = true);
+ERROR:  cannot enable failover for a two_phase enabled subscription
 ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
 DROP SUBSCRIPTION regress_testsub;
 -- two_phase and streaming are compatible.
@@ -479,6 +482,9 @@ COMMIT;
 ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
 DROP SUBSCRIPTION regress_testsub;
 RESET SESSION AUTHORIZATION;
+-- fail - cannot enable two_phase and failover together
+CREATE SUBSCRIPTION regress_testsub CONNECTION 'dbname=regress_doesnotexist' PUBLICATION testpub WITH (connect = false, two_phase = true, failover = true);
+ERROR:  "failover" and "two_phase" are mutually exclusive options
 DROP ROLE regress_subscription_user;
 DROP ROLE regress_subscription_user2;
 DROP ROLE regress_subscription_user3;
diff --git a/src/test/regress/sql/subscription.sql b/src/test/regress/sql/subscription.sql
index 3e5ba4cb8c6..bc6e0f04e64 100644
--- a/src/test/regress/sql/subscription.sql
+++ b/src/test/regress/sql/subscription.sql
@@ -264,6 +264,9 @@ ALTER SUBSCRIPTION regress_testsub SET (streaming = true);
 
 \dRs+
 
+--fail - cannot enable failover for a two_phase enabled subscription
+ALTER SUBSCRIPTION regress_testsub SET (failover = true);
+
 ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
 DROP SUBSCRIPTION regress_testsub;
 
@@ -342,6 +345,10 @@ ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
 DROP SUBSCRIPTION regress_testsub;
 
 RESET SESSION AUTHORIZATION;
+
+-- fail - cannot enable two_phase and failover together
+CREATE SUBSCRIPTION regress_testsub CONNECTION 'dbname=regress_doesnotexist' PUBLICATION testpub WITH (connect = false, two_phase = true, failover = true);
+
 DROP ROLE regress_subscription_user;
 DROP ROLE regress_subscription_user2;
 DROP ROLE regress_subscription_user3;
-- 
2.31.1



^ permalink  raw  reply  [nested|flat] 88+ messages in thread

end of thread, other threads:[~2025-04-02 05:55 UTC | newest]

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2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v4] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v5 2/3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v3] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2021-01-18 05:47 [PATCH v2] Do not use RelationNeedsWAL to identify relation persistence Kyotaro Horiguchi <[email protected]>
2025-04-01 06:09 Re: Fix slot synchronization with two_phase decoding enabled Amit Kapila <[email protected]>
2025-04-01 10:58 ` RE: Fix slot synchronization with two_phase decoding enabled Zhijie Hou (Fujitsu) <[email protected]>
2025-04-02 04:40   ` Re: Fix slot synchronization with two_phase decoding enabled Amit Kapila <[email protected]>
2025-04-02 05:55     ` RE: Fix slot synchronization with two_phase decoding enabled Zhijie Hou (Fujitsu) <[email protected]>

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