Re: [HACKERS] WAL logging problem in 9.4.3?

Hello.

At Thu, 16 May 2019 23:50:50 -0700, Noah Misch <noah@leadboat.com> wrote in
<20190517065050.GA1298884@rfd.leadboat.com>
> On Tue, May 14, 2019 at 01:59:10PM +0900, Kyotaro HORIGUCHI wrote:
> > At Sun, 12 May 2019 17:37:05 -0700, Noah Misch <noah@leadboat.com> wrote in
<20190513003705.GA1202614@rfd.leadboat.com>
> > > On Sun, Mar 31, 2019 at 03:31:58PM -0700, Noah Misch wrote:
> > > > On Sun, Mar 10, 2019 at 07:27:08PM -0700, Noah Misch wrote:
> > > > > I also liked the design in the https://postgr.es/m/559FA0BA.3080808@iki.fi
> > > > > last paragraph, and I suspect it would have been no harder to back-patch.  I
> > > > > wonder if it would have been simpler and better, but I'm not asking anyone to
> > > > > investigate that.
> > > > 
> > > > Now I am asking for that.  Would anyone like to try implementing that other
> > > > design, to see how much simpler it would be?
> > 
> > Yeah, I think it is a bit too-complex for the value. But I think
> > it is the best way as far as we keep reusing a file on
> > truncation of the whole file.
> 
> The design of v11-0006-Fix-WAL-skipping-feature.patch doesn't, in general,
> work for WAL records touching more than one buffer.  For heapam, that patch
> works around this problem by emitting XLOG_HEAP_INSERT or XLOG_HEAP_DELETE
> when we'd normally emit XLOG_HEAP_UPDATE.  As a result, post-crash-recovery
> heap page bits differ from the bits present when we don't crash.  Though I'm
> 85% confident this does not introduce a bug today, this is fragile.  That is
> the main complexity I wish to avoid.

Ok, I see your point. The same issue happens on index pages more
aggressively. I didn't allow wal-skipping on indexes for the
reason.

> I suspect the design in the https://postgr.es/m/559FA0BA.3080808@iki.fi last
> paragraph will be simpler, not more complex.  In the implementation I'm
> envisioning, smgrDoPendingDeletes() would change name, perhaps to
> AtEOXact_Storage().  For every relfilenode it does not delete, it would ensure
> durability by syncing (for large nodes) or by WAL-logging each page (for small
> nodes).  RelationNeedsWAL() would return false whenever the applicable
> relfilenode appears in pendingDeletes.  Access methods would remove their
> smgrimmedsync() calls, but they would otherwise not change.  Would anyone like
> to try implementing that?

Following this direction, the attached PoC works *at least for*
the wal_optimization TAP tests, but doing pending flush not in
smgr but in relcache. This is extending skip-wal feature to
indexes. And makes the old 0002 patch on nbtree useless.

regards.

-- 
Kyotaro Horiguchi
NTT Open Source Software Center
From ebca88dea9f9458cbd58f15e370ff3fc8fbd371b Mon Sep 17 00:00:00 2001
From: Kyotaro Horiguchi <horiguchi.kyotaro@lab.ntt.co.jp>
Date: Thu, 11 Oct 2018 10:03:21 +0900
Subject: [PATCH 1/2] TAP test for copy-truncation optimization.

---
 src/test/recovery/t/018_wal_optimize.pl | 291 ++++++++++++++++++++++++++++++++
 1 file changed, 291 insertions(+)
 create mode 100644 src/test/recovery/t/018_wal_optimize.pl

diff --git a/src/test/recovery/t/018_wal_optimize.pl b/src/test/recovery/t/018_wal_optimize.pl
new file mode 100644
index 0000000000..4fa8be728e
--- /dev/null
+++ b/src/test/recovery/t/018_wal_optimize.pl
@@ -0,0 +1,291 @@
+# Test WAL replay for optimized TRUNCATE and COPY records
+#
+# WAL truncation is optimized in some cases with TRUNCATE and COPY queries
+# which sometimes interact badly with the other optimizations in line with
+# several setting values of wal_level, particularly when using "minimal" or
+# "replica".  The optimization may be enabled or disabled depending on the
+# scenarios dealt here, and should never result in any type of failures or
+# data loss.
+use strict;
+use warnings;
+
+use PostgresNode;
+use TestLib;
+use Test::More tests => 24;
+
+sub check_orphan_relfilenodes
+{
+    my($node, $test_name) = @_;
+
+    my $db_oid = $node->safe_psql('postgres',
+       "SELECT oid FROM pg_database WHERE datname = 'postgres'");
+    my $prefix = "base/$db_oid/";
+    my $filepaths_referenced = $node->safe_psql('postgres', "
+       SELECT pg_relation_filepath(oid) FROM pg_class
+       WHERE reltablespace = 0 and relpersistence <> 't' and
+       pg_relation_filepath(oid) IS NOT NULL;");
+    is_deeply([sort(map { "$prefix$_" }
+                    grep(/^[0-9]+$/,
+                         slurp_dir($node->data_dir . "/$prefix")))],
+              [sort split /\n/, $filepaths_referenced],
+              $test_name);
+    return;
+}
+
+# Wrapper routine tunable for wal_level.
+sub run_wal_optimize
+{
+    my $wal_level = shift;
+
+    # Primary needs to have wal_level = minimal here
+    my $node = get_new_node("node_$wal_level");
+    $node->init;
+    $node->append_conf('postgresql.conf', qq(
+wal_level = $wal_level
+));
+    $node->start;
+
+    # Setup
+    my $tablespace_dir = $node->basedir . '/tablespace_other';
+    mkdir ($tablespace_dir);
+    $tablespace_dir = TestLib::real_dir($tablespace_dir);
+    $node->safe_psql('postgres',
+       "CREATE TABLESPACE other LOCATION '$tablespace_dir';");
+
+    # Test direct truncation optimization.  No tuples
+    $node->safe_psql('postgres', "
+        BEGIN;
+        CREATE TABLE test1 (id serial PRIMARY KEY);
+        TRUNCATE test1;
+        COMMIT;");
+
+    $node->stop('immediate');
+    $node->start;
+
+    my $result = $node->safe_psql('postgres', "SELECT count(*) FROM test1;");
+    is($result, qq(0),
+       "wal_level = $wal_level, optimized truncation with empty table");
+
+    # Test truncation with inserted tuples within the same transaction.
+    # Tuples inserted after the truncation should be seen.
+    $node->safe_psql('postgres', "
+        BEGIN;
+        CREATE TABLE test2 (id serial PRIMARY KEY);
+        INSERT INTO test2 VALUES (DEFAULT);
+        TRUNCATE test2;
+        INSERT INTO test2 VALUES (DEFAULT);
+        COMMIT;");
+
+    $node->stop('immediate');
+    $node->start;
+
+    $result = $node->safe_psql('postgres', "SELECT count(*) FROM test2;");
+    is($result, qq(1),
+       "wal_level = $wal_level, optimized truncation with inserted table");
+
+    # Data file for COPY query in follow-up tests.
+    my $basedir = $node->basedir;
+    my $copy_file = "$basedir/copy_data.txt";
+    TestLib::append_to_file($copy_file, qq(20000,30000
+20001,30001
+20002,30002));
+
+    # Test truncation with inserted tuples using COPY.  Tuples copied after the
+    # truncation should be seen.
+    $node->safe_psql('postgres', "
+        BEGIN;
+        CREATE TABLE test3 (id serial PRIMARY KEY, id2 int);
+        INSERT INTO test3 (id, id2) VALUES (DEFAULT, generate_series(1,3000));
+        TRUNCATE test3;
+        COPY test3 FROM '$copy_file' DELIMITER ',';
+        COMMIT;");
+    $node->stop('immediate');
+    $node->start;
+    $result = $node->safe_psql('postgres', "SELECT count(*) FROM test3;");
+    is($result, qq(3),
+       "wal_level = $wal_level, optimized truncation with copied table");
+
+    # Like previous test, but rollback SET TABLESPACE in a subtransaction.
+    $node->safe_psql('postgres', "
+        BEGIN;
+        CREATE TABLE test3a (id serial PRIMARY KEY, id2 int);
+        INSERT INTO test3a (id, id2) VALUES (DEFAULT, generate_series(1,3000));
+        TRUNCATE test3a;
+        SAVEPOINT s; ALTER TABLE test3a SET TABLESPACE other; ROLLBACK TO s;
+        COPY test3a FROM '$copy_file' DELIMITER ',';
+        COMMIT;");
+    $node->stop('immediate');
+    $node->start;
+    $result = $node->safe_psql('postgres', "SELECT count(*) FROM test3a;");
+    is($result, qq(3),
+       "wal_level = $wal_level, SET TABLESPACE in subtransaction");
+
+    # in different subtransaction patterns
+    $node->safe_psql('postgres', "
+        BEGIN;
+        CREATE TABLE test3a2 (id serial PRIMARY KEY, id2 int);
+        INSERT INTO test3a2 (id, id2) VALUES (DEFAULT, generate_series(1,3000));
+        TRUNCATE test3a2;
+        SAVEPOINT s; ALTER TABLE test3a SET TABLESPACE other; RELEASE s;
+        COPY test3a2 FROM '$copy_file' DELIMITER ',';
+        COMMIT;");
+    $node->stop('immediate');
+    $node->start;
+    $result = $node->safe_psql('postgres', "SELECT count(*) FROM test3a;");
+    is($result, qq(3),
+       "wal_level = $wal_level, SET TABLESPACE in subtransaction");
+
+    $node->safe_psql('postgres', "
+        BEGIN;
+        CREATE TABLE test3a3 (id serial PRIMARY KEY, id2 int);
+        INSERT INTO test3a3 (id, id2) VALUES (DEFAULT, generate_series(1,3000));
+        TRUNCATE test3a3;
+        SAVEPOINT s;
+            ALTER TABLE test3a3 SET TABLESPACE other;
+            SAVEPOINT s2;
+                ALTER TABLE test3a3 SET TABLESPACE pg_default;
+            ROLLBACK TO s2;
+            SAVEPOINT s2;
+                ALTER TABLE test3a3 SET TABLESPACE pg_default;
+            RELEASE s2;
+        ROLLBACK TO s;
+        COPY test3a3 FROM '$copy_file' DELIMITER ',';
+        COMMIT;");
+    $node->stop('immediate');
+    $node->start;
+    $result = $node->safe_psql('postgres', "SELECT count(*) FROM test3a;");
+    is($result, qq(3),
+       "wal_level = $wal_level, SET TABLESPACE in subtransaction");
+
+    # UPDATE touches two buffers; one is BufferNeedsWAL(); the other is not.
+    $node->safe_psql('postgres', "
+        BEGIN;
+        CREATE TABLE test3b (id serial PRIMARY KEY, id2 int);
+        INSERT INTO test3b (id, id2) VALUES (DEFAULT, generate_series(1,10000));
+        COPY test3b FROM '$copy_file' DELIMITER ',';  -- set sync_above
+        UPDATE test3b SET id2 = id2 + 1;
+        DELETE FROM test3b;
+        COMMIT;");
+    $node->stop('immediate');
+    $node->start;
+    $result = $node->safe_psql('postgres', "SELECT count(*) FROM test3b;");
+    is($result, qq(0),
+       "wal_level = $wal_level, UPDATE of logged page extends relation");
+
+    # Test truncation with inserted tuples using both INSERT and COPY. Tuples
+    # inserted after the truncation should be seen.
+    $node->safe_psql('postgres', "
+        BEGIN;
+        CREATE TABLE test4 (id serial PRIMARY KEY, id2 int);
+        INSERT INTO test4 (id, id2) VALUES (DEFAULT, generate_series(1,10000));
+        TRUNCATE test4;
+        INSERT INTO test4 (id, id2) VALUES (DEFAULT, 10000);
+        COPY test4 FROM '$copy_file' DELIMITER ',';
+        INSERT INTO test4 (id, id2) VALUES (DEFAULT, 10000);
+        COMMIT;");
+
+    $node->stop('immediate');
+    $node->start;
+    $result = $node->safe_psql('postgres', "SELECT count(*) FROM test4;");
+    is($result, qq(5),
+       "wal_level = $wal_level, optimized truncation with inserted/copied table");
+
+    # Test consistency of COPY with INSERT for table created in the same
+    # transaction.
+    $node->safe_psql('postgres', "
+        BEGIN;
+        CREATE TABLE test5 (id serial PRIMARY KEY, id2 int);
+        INSERT INTO test5 VALUES (DEFAULT, 1);
+        COPY test5 FROM '$copy_file' DELIMITER ',';
+        COMMIT;");
+    $node->stop('immediate');
+    $node->start;
+    $result = $node->safe_psql('postgres', "SELECT count(*) FROM test5;");
+    is($result, qq(4),
+       "wal_level = $wal_level, replay of optimized copy with inserted table");
+
+    # Test consistency of COPY that inserts more to the same table using
+    # triggers.  If the INSERTS from the trigger go to the same block data
+    # is copied to, and the INSERTs are WAL-logged, WAL replay will fail when
+    # it tries to replay the WAL record but the "before" image doesn't match,
+    # because not all changes were WAL-logged.
+    $node->safe_psql('postgres', "
+        BEGIN;
+        CREATE TABLE test6 (id serial PRIMARY KEY, id2 text);
+        CREATE FUNCTION test6_before_row_trig() RETURNS trigger
+          LANGUAGE plpgsql as \$\$
+          BEGIN
+            IF new.id2 NOT LIKE 'triggered%' THEN
+              INSERT INTO test6 VALUES (DEFAULT, 'triggered row before' || NEW.id2);
+            END IF;
+            RETURN NEW;
+          END; \$\$;
+        CREATE FUNCTION test6_after_row_trig() RETURNS trigger
+          LANGUAGE plpgsql as \$\$
+          BEGIN
+            IF new.id2 NOT LIKE 'triggered%' THEN
+              INSERT INTO test6 VALUES (DEFAULT, 'triggered row after' || OLD.id2);
+            END IF;
+            RETURN NEW;
+          END; \$\$;
+        CREATE TRIGGER test6_before_row_insert
+          BEFORE INSERT ON test6
+          FOR EACH ROW EXECUTE PROCEDURE test6_before_row_trig();
+        CREATE TRIGGER test6_after_row_insert
+          AFTER INSERT ON test6
+          FOR EACH ROW EXECUTE PROCEDURE test6_after_row_trig();
+        COPY test6 FROM '$copy_file' DELIMITER ',';
+        COMMIT;");
+    $node->stop('immediate');
+    $node->start;
+    $result = $node->safe_psql('postgres', "SELECT count(*) FROM test6;");
+    is($result, qq(9),
+       "wal_level = $wal_level, replay of optimized copy with before trigger");
+
+    # Test consistency of INSERT, COPY and TRUNCATE in same transaction block
+    # with TRUNCATE triggers.
+    $node->safe_psql('postgres', "
+        BEGIN;
+        CREATE TABLE test7 (id serial PRIMARY KEY, id2 text);
+        CREATE FUNCTION test7_before_stat_trig() RETURNS trigger
+          LANGUAGE plpgsql as \$\$
+          BEGIN
+            INSERT INTO test7 VALUES (DEFAULT, 'triggered stat before');
+            RETURN NULL;
+          END; \$\$;
+        CREATE FUNCTION test7_after_stat_trig() RETURNS trigger
+          LANGUAGE plpgsql as \$\$
+          BEGIN
+            INSERT INTO test7 VALUES (DEFAULT, 'triggered stat before');
+            RETURN NULL;
+          END; \$\$;
+        CREATE TRIGGER test7_before_stat_truncate
+          BEFORE TRUNCATE ON test7
+          FOR EACH STATEMENT EXECUTE PROCEDURE test7_before_stat_trig();
+        CREATE TRIGGER test7_after_stat_truncate
+          AFTER TRUNCATE ON test7
+          FOR EACH STATEMENT EXECUTE PROCEDURE test7_after_stat_trig();
+        INSERT INTO test7 VALUES (DEFAULT, 1);
+        TRUNCATE test7;
+        COPY test7 FROM '$copy_file' DELIMITER ',';
+        COMMIT;");
+    $node->stop('immediate');
+    $node->start;
+    $result = $node->safe_psql('postgres', "SELECT count(*) FROM test7;");
+    is($result, qq(4),
+       "wal_level = $wal_level, replay of optimized copy with before trigger");
+
+    # Test redo of temp table creation.
+    $node->safe_psql('postgres', "
+        CREATE TEMP TABLE test8 (id serial PRIMARY KEY, id2 text);");
+    $node->stop('immediate');
+    $node->start;
+
+    check_orphan_relfilenodes($node, "wal_level = $wal_level, no orphan relfilenode remains");
+
+    return;
+}
+
+# Run same test suite for multiple wal_level values.
+run_wal_optimize("minimal");
+run_wal_optimize("replica");
-- 
2.16.3

From 3859609090a274fc1ba59964f3819d19217bd8ef Mon Sep 17 00:00:00 2001
From: Kyotaro Horiguchi <horiguchi.kyotaro@lab.ntt.co.jp>
Date: Mon, 20 May 2019 15:38:59 +0900
Subject: [PATCH 2/2] Fix WAL skipping feature

This patch shows a PoC of how change WAL-skipping feature to avoid
table corruption caused by mixing wal-logged and wal-skipped
operations.
---
 src/backend/access/heap/heapam.c         |  4 ++--
 src/backend/access/heap/heapam_handler.c |  7 +------
 src/backend/access/heap/rewriteheap.c    |  3 ---
 src/backend/access/transam/xact.c        |  6 ++++++
 src/backend/commands/copy.c              |  4 ----
 src/backend/commands/createas.c          |  3 +--
 src/backend/commands/tablecmds.c         |  2 --
 src/backend/utils/cache/relcache.c       | 22 ++++++++++++++++++++++
 src/include/access/heapam.h              |  1 -
 src/include/utils/rel.h                  |  3 ++-
 src/include/utils/relcache.h             |  1 +
 11 files changed, 35 insertions(+), 21 deletions(-)

diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index 19d2c529d8..dda76c8736 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -1950,7 +1950,7 @@ heap_insert(Relation relation, HeapTuple tup, CommandId cid,
     MarkBufferDirty(buffer);
 
     /* XLOG stuff */
-    if (!(options & HEAP_INSERT_SKIP_WAL) && RelationNeedsWAL(relation))
+    if (RelationNeedsWAL(relation))
     {
         xl_heap_insert xlrec;
         xl_heap_header xlhdr;
@@ -2133,7 +2133,7 @@ heap_multi_insert(Relation relation, TupleTableSlot **slots, int ntuples,
     /* currently not needed (thus unsupported) for heap_multi_insert() */
     AssertArg(!(options & HEAP_INSERT_NO_LOGICAL));
 
-    needwal = !(options & HEAP_INSERT_SKIP_WAL) && RelationNeedsWAL(relation);
+    needwal = RelationNeedsWAL(relation);
     saveFreeSpace = RelationGetTargetPageFreeSpace(relation,
                                                    HEAP_DEFAULT_FILLFACTOR);
 
diff --git a/src/backend/access/heap/heapam_handler.c b/src/backend/access/heap/heapam_handler.c
index 8d8161fd97..f4af981a35 100644
--- a/src/backend/access/heap/heapam_handler.c
+++ b/src/backend/access/heap/heapam_handler.c
@@ -560,12 +560,7 @@ tuple_lock_retry:
 static void
 heapam_finish_bulk_insert(Relation relation, int options)
 {
-    /*
-     * If we skipped writing WAL, then we need to sync the heap (but not
-     * indexes since those use WAL anyway / don't go through tableam)
-     */
-    if (options & HEAP_INSERT_SKIP_WAL)
-        heap_sync(relation);
+    /* heapam doesn't need do this */
 }
 
 
diff --git a/src/backend/access/heap/rewriteheap.c b/src/backend/access/heap/rewriteheap.c
index bce4274362..1ac77f7c14 100644
--- a/src/backend/access/heap/rewriteheap.c
+++ b/src/backend/access/heap/rewriteheap.c
@@ -654,9 +654,6 @@ raw_heap_insert(RewriteState state, HeapTuple tup)
     {
         int options = HEAP_INSERT_SKIP_FSM;
 
-        if (!state->rs_use_wal)
-            options |= HEAP_INSERT_SKIP_WAL;
-
         /*
          * While rewriting the heap for VACUUM FULL / CLUSTER, make sure data
          * for the TOAST table are not logically decoded.  The main heap is
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 20feeec327..fb35992a13 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -2133,6 +2133,9 @@ CommitTransaction(void)
     /* Commit updates to the relation map --- do this as late as possible */
     AtEOXact_RelationMap(true, is_parallel_worker);
 
+    /* Perform pending flush */
+    AtEOXact_DoPendingFlush();
+
     /*
      * set the current transaction state information appropriately during
      * commit processing
@@ -2349,6 +2352,9 @@ PrepareTransaction(void)
      */
     PreCommit_CheckForSerializationFailure();
 
+    /* Perform pending flush */
+    AtEOXact_DoPendingFlush();
+
     /* NOTIFY will be handled below */
 
     /*
diff --git a/src/backend/commands/copy.c b/src/backend/commands/copy.c
index 6ffc3a62f6..9bae04b8a7 100644
--- a/src/backend/commands/copy.c
+++ b/src/backend/commands/copy.c
@@ -2761,11 +2761,7 @@ CopyFrom(CopyState cstate)
     if (RELKIND_HAS_STORAGE(cstate->rel->rd_rel->relkind) &&
         (cstate->rel->rd_createSubid != InvalidSubTransactionId ||
          cstate->rel->rd_newRelfilenodeSubid != InvalidSubTransactionId))
-    {
         ti_options |= TABLE_INSERT_SKIP_FSM;
-        if (!XLogIsNeeded())
-            ti_options |= TABLE_INSERT_SKIP_WAL;
-    }
 
     /*
      * Optimize if new relfilenode was created in this subxact or one of its
diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c
index 43c2fa9124..83e5f9220f 100644
--- a/src/backend/commands/createas.c
+++ b/src/backend/commands/createas.c
@@ -558,8 +558,7 @@ intorel_startup(DestReceiver *self, int operation, TupleDesc typeinfo)
      * We can skip WAL-logging the insertions, unless PITR or streaming
      * replication is in use. We can skip the FSM in any case.
      */
-    myState->ti_options = TABLE_INSERT_SKIP_FSM |
-        (XLogIsNeeded() ? 0 : TABLE_INSERT_SKIP_WAL);
+    myState->ti_options = TABLE_INSERT_SKIP_FSM;
     myState->bistate = GetBulkInsertState();
 
     /* Not using WAL requires smgr_targblock be initially invalid */
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index bfcf9472d7..b686497443 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -4741,8 +4741,6 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap, LOCKMODE lockmode)
         bistate = GetBulkInsertState();
 
         ti_options = TABLE_INSERT_SKIP_FSM;
-        if (!XLogIsNeeded())
-            ti_options |= TABLE_INSERT_SKIP_WAL;
     }
     else
     {
diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c
index d0f6f715e6..10fd405171 100644
--- a/src/backend/utils/cache/relcache.c
+++ b/src/backend/utils/cache/relcache.c
@@ -2913,6 +2913,28 @@ RememberToFreeTupleDescAtEOX(TupleDesc td)
     EOXactTupleDescArray[NextEOXactTupleDescNum++] = td;
 }
 
+void
+AtEOXact_DoPendingFlush()
+{
+    HASH_SEQ_STATUS status;
+    RelIdCacheEnt *idhentry;
+
+    if (!RelationIdCache)
+        return;
+
+    hash_seq_init(&status, RelationIdCache);
+    while ((idhentry = (RelIdCacheEnt *) hash_seq_search(&status)) != NULL)
+    {
+        Relation rel = idhentry->reldesc;
+        if (RELATION_IS_LOCAL(rel) && !XLogIsNeeded() && rel->rd_smgr)
+        {
+            FlushRelationBuffers(rel);
+            smgrimmedsync(rel->rd_smgr, MAIN_FORKNUM);
+        }
+    }
+}
+
+
 /*
  * AtEOXact_RelationCache
  *
diff --git a/src/include/access/heapam.h b/src/include/access/heapam.h
index 62aaa08eff..0fb7d86bf2 100644
--- a/src/include/access/heapam.h
+++ b/src/include/access/heapam.h
@@ -29,7 +29,6 @@
 
 
 /* "options" flag bits for heap_insert */
-#define HEAP_INSERT_SKIP_WAL    TABLE_INSERT_SKIP_WAL
 #define HEAP_INSERT_SKIP_FSM    TABLE_INSERT_SKIP_FSM
 #define HEAP_INSERT_FROZEN        TABLE_INSERT_FROZEN
 #define HEAP_INSERT_NO_LOGICAL    TABLE_INSERT_NO_LOGICAL
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index d7f33abce3..41ab634ff5 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -514,7 +514,8 @@ typedef struct ViewOptions
  *        True if relation needs WAL.
  */
 #define RelationNeedsWAL(relation) \
-    ((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
+    ((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT && \
+     !(RELATION_IS_LOCAL(relation) && !XLogIsNeeded()))
 
 /*
  * RelationUsesLocalBuffers
diff --git a/src/include/utils/relcache.h b/src/include/utils/relcache.h
index 364495a5f0..cd9b1a6f68 100644
--- a/src/include/utils/relcache.h
+++ b/src/include/utils/relcache.h
@@ -123,6 +123,7 @@ extern void RelationCloseSmgrByOid(Oid relationId);
 extern void AtEOXact_RelationCache(bool isCommit);
 extern void AtEOSubXact_RelationCache(bool isCommit, SubTransactionId mySubid,
                           SubTransactionId parentSubid);
+extern void AtEOXact_DoPendingFlush(void);
 
 /*
  * Routines to help manage rebuilding of relcache init files
-- 
2.16.3