bool amcaninclude;
/* does AM use maintenance_work_mem? */
bool amusemaintenanceworkmem;
+ /* does AM block HOT update? */
+ bool amhotblocking;
/* OR of parallel vacuum flags */
uint8 amparallelvacuumoptions;
/* type of data stored in index, or InvalidOid if variable */
null, independently of <structfield>amoptionalkey</structfield>.
</para>
+ <para>
+ The <structfield>amhotblocking</structfield> flag indicates whether the
+ access method blocks <acronym>HOT</acronym> when an indexed attribute is
+ updated. Access methods without pointers to individual tuples (like
+ <acronym>BRIN</acronym>) may allow <acronym>HOT</acronym> even in this
+ case. This does not apply to attributes referenced in index predicates,
+ an update of such attribute always disables <acronym>HOT</acronym>.
+ </para>
+
</sect1>
<sect1 id="index-functions">
amroutine->amcanparallel = false;
amroutine->amcaninclude = false;
amroutine->amusemaintenanceworkmem = false;
+ amroutine->amhotblocking = false;
amroutine->amparallelvacuumoptions =
VACUUM_OPTION_PARALLEL_CLEANUP;
amroutine->amkeytype = InvalidOid;
amroutine->amcanparallel = false;
amroutine->amcaninclude = false;
amroutine->amusemaintenanceworkmem = true;
+ amroutine->amhotblocking = true;
amroutine->amparallelvacuumoptions =
VACUUM_OPTION_PARALLEL_BULKDEL | VACUUM_OPTION_PARALLEL_CLEANUP;
amroutine->amkeytype = InvalidOid;
amroutine->amcanparallel = false;
amroutine->amcaninclude = true;
amroutine->amusemaintenanceworkmem = false;
+ amroutine->amhotblocking = true;
amroutine->amparallelvacuumoptions =
VACUUM_OPTION_PARALLEL_BULKDEL | VACUUM_OPTION_PARALLEL_COND_CLEANUP;
amroutine->amkeytype = InvalidOid;
amroutine->amcanparallel = false;
amroutine->amcaninclude = false;
amroutine->amusemaintenanceworkmem = false;
+ amroutine->amhotblocking = true;
amroutine->amparallelvacuumoptions =
VACUUM_OPTION_PARALLEL_BULKDEL;
amroutine->amkeytype = INT4OID;
* Note that we get copies of each bitmap, so we need not worry about
* relcache flush happening midway through.
*/
- hot_attrs = RelationGetIndexAttrBitmap(relation, INDEX_ATTR_BITMAP_ALL);
+ hot_attrs = RelationGetIndexAttrBitmap(relation, INDEX_ATTR_BITMAP_HOT_BLOCKING);
key_attrs = RelationGetIndexAttrBitmap(relation, INDEX_ATTR_BITMAP_KEY);
id_attrs = RelationGetIndexAttrBitmap(relation,
INDEX_ATTR_BITMAP_IDENTITY_KEY);
amroutine->amcanparallel = true;
amroutine->amcaninclude = true;
amroutine->amusemaintenanceworkmem = false;
+ amroutine->amhotblocking = true;
amroutine->amparallelvacuumoptions =
VACUUM_OPTION_PARALLEL_BULKDEL | VACUUM_OPTION_PARALLEL_COND_CLEANUP;
amroutine->amkeytype = InvalidOid;
amroutine->amcanparallel = false;
amroutine->amcaninclude = true;
amroutine->amusemaintenanceworkmem = false;
+ amroutine->amhotblocking = true;
amroutine->amparallelvacuumoptions =
VACUUM_OPTION_PARALLEL_BULKDEL | VACUUM_OPTION_PARALLEL_COND_CLEANUP;
amroutine->amkeytype = InvalidOid;
list_free_deep(relation->rd_fkeylist);
list_free(relation->rd_indexlist);
list_free(relation->rd_statlist);
- bms_free(relation->rd_indexattr);
bms_free(relation->rd_keyattr);
bms_free(relation->rd_pkattr);
bms_free(relation->rd_idattr);
+ bms_free(relation->rd_hotblockingattr);
if (relation->rd_pubactions)
pfree(relation->rd_pubactions);
if (relation->rd_options)
Bitmapset *
RelationGetIndexAttrBitmap(Relation relation, IndexAttrBitmapKind attrKind)
{
- Bitmapset *indexattrs; /* indexed columns */
Bitmapset *uindexattrs; /* columns in unique indexes */
Bitmapset *pkindexattrs; /* columns in the primary index */
Bitmapset *idindexattrs; /* columns in the replica identity */
+ Bitmapset *hotblockingattrs; /* columns with HOT blocking indexes */
List *indexoidlist;
List *newindexoidlist;
Oid relpkindex;
MemoryContext oldcxt;
/* Quick exit if we already computed the result. */
- if (relation->rd_indexattr != NULL)
+ if (relation->rd_attrsvalid)
{
switch (attrKind)
{
- case INDEX_ATTR_BITMAP_ALL:
- return bms_copy(relation->rd_indexattr);
case INDEX_ATTR_BITMAP_KEY:
return bms_copy(relation->rd_keyattr);
case INDEX_ATTR_BITMAP_PRIMARY_KEY:
return bms_copy(relation->rd_pkattr);
case INDEX_ATTR_BITMAP_IDENTITY_KEY:
return bms_copy(relation->rd_idattr);
+ case INDEX_ATTR_BITMAP_HOT_BLOCKING:
+ return bms_copy(relation->rd_hotblockingattr);
default:
elog(ERROR, "unknown attrKind %u", attrKind);
}
relreplindex = relation->rd_replidindex;
/*
- * For each index, add referenced attributes to indexattrs.
+ * For each index, add referenced attributes to appropriate bitmaps.
*
* Note: we consider all indexes returned by RelationGetIndexList, even if
* they are not indisready or indisvalid. This is important because an
* CONCURRENTLY is far enough along that we should ignore the index, it
* won't be returned at all by RelationGetIndexList.
*/
- indexattrs = NULL;
uindexattrs = NULL;
pkindexattrs = NULL;
idindexattrs = NULL;
+ hotblockingattrs = NULL;
foreach(l, indexoidlist)
{
Oid indexOid = lfirst_oid(l);
*/
if (attrnum != 0)
{
- indexattrs = bms_add_member(indexattrs,
- attrnum - FirstLowInvalidHeapAttributeNumber);
+ if (indexDesc->rd_indam->amhotblocking)
+ hotblockingattrs = bms_add_member(hotblockingattrs,
+ attrnum - FirstLowInvalidHeapAttributeNumber);
if (isKey && i < indexDesc->rd_index->indnkeyatts)
uindexattrs = bms_add_member(uindexattrs,
}
/* Collect all attributes used in expressions, too */
- pull_varattnos(indexExpressions, 1, &indexattrs);
+ if (indexDesc->rd_indam->amhotblocking)
+ pull_varattnos(indexExpressions, 1, &hotblockingattrs);
- /* Collect all attributes in the index predicate, too */
- pull_varattnos(indexPredicate, 1, &indexattrs);
+ /*
+ * Collect all attributes in the index predicate, too. We have to ignore
+ * amhotblocking flag, because the row might become indexable, in which
+ * case we have to add it to the index.
+ */
+ pull_varattnos(indexPredicate, 1, &hotblockingattrs);
index_close(indexDesc, AccessShareLock);
}
bms_free(uindexattrs);
bms_free(pkindexattrs);
bms_free(idindexattrs);
- bms_free(indexattrs);
+ bms_free(hotblockingattrs);
goto restart;
}
/* Don't leak the old values of these bitmaps, if any */
- bms_free(relation->rd_indexattr);
- relation->rd_indexattr = NULL;
bms_free(relation->rd_keyattr);
relation->rd_keyattr = NULL;
bms_free(relation->rd_pkattr);
relation->rd_pkattr = NULL;
bms_free(relation->rd_idattr);
relation->rd_idattr = NULL;
+ bms_free(relation->rd_hotblockingattr);
+ relation->rd_hotblockingattr = NULL;
/*
* Now save copies of the bitmaps in the relcache entry. We intentionally
- * set rd_indexattr last, because that's the one that signals validity of
- * the values; if we run out of memory before making that copy, we won't
+ * set rd_attrsvalid last, because that's what signals validity of the
+ * values; if we run out of memory before making that copy, we won't
* leave the relcache entry looking like the other ones are valid but
* empty.
*/
relation->rd_keyattr = bms_copy(uindexattrs);
relation->rd_pkattr = bms_copy(pkindexattrs);
relation->rd_idattr = bms_copy(idindexattrs);
- relation->rd_indexattr = bms_copy(indexattrs);
+ relation->rd_hotblockingattr = bms_copy(hotblockingattrs);
+ relation->rd_attrsvalid = true;
MemoryContextSwitchTo(oldcxt);
/* We return our original working copy for caller to play with */
switch (attrKind)
{
- case INDEX_ATTR_BITMAP_ALL:
- return indexattrs;
case INDEX_ATTR_BITMAP_KEY:
return uindexattrs;
case INDEX_ATTR_BITMAP_PRIMARY_KEY:
return pkindexattrs;
case INDEX_ATTR_BITMAP_IDENTITY_KEY:
return idindexattrs;
+ case INDEX_ATTR_BITMAP_HOT_BLOCKING:
+ return hotblockingattrs;
default:
elog(ERROR, "unknown attrKind %u", attrKind);
return NULL;
rel->rd_indexlist = NIL;
rel->rd_pkindex = InvalidOid;
rel->rd_replidindex = InvalidOid;
- rel->rd_indexattr = NULL;
+ rel->rd_attrsvalid = false;
rel->rd_keyattr = NULL;
rel->rd_pkattr = NULL;
rel->rd_idattr = NULL;
+ rel->rd_hotblockingattr = NULL;
rel->rd_pubactions = NULL;
rel->rd_statvalid = false;
rel->rd_statlist = NIL;
bool amcaninclude;
/* does AM use maintenance_work_mem? */
bool amusemaintenanceworkmem;
+ /* does AM block HOT update? */
+ bool amhotblocking;
/* OR of parallel vacuum flags. See vacuum.h for flags. */
uint8 amparallelvacuumoptions;
/* type of data stored in index, or InvalidOid if variable */
List *rd_statlist; /* list of OIDs of extended stats */
/* data managed by RelationGetIndexAttrBitmap: */
- Bitmapset *rd_indexattr; /* identifies columns used in indexes */
+ bool rd_attrsvalid; /* are bitmaps of attrs valid? */
Bitmapset *rd_keyattr; /* cols that can be ref'd by foreign keys */
Bitmapset *rd_pkattr; /* cols included in primary key */
Bitmapset *rd_idattr; /* included in replica identity index */
+ Bitmapset *rd_hotblockingattr; /* cols blocking HOT update */
PublicationActions *rd_pubactions; /* publication actions */
typedef enum IndexAttrBitmapKind
{
- INDEX_ATTR_BITMAP_ALL,
INDEX_ATTR_BITMAP_KEY,
INDEX_ATTR_BITMAP_PRIMARY_KEY,
- INDEX_ATTR_BITMAP_IDENTITY_KEY
+ INDEX_ATTR_BITMAP_IDENTITY_KEY,
+ INDEX_ATTR_BITMAP_HOT_BLOCKING
} IndexAttrBitmapKind;
extern Bitmapset *RelationGetIndexAttrBitmap(Relation relation,
amroutine->amcanparallel = false;
amroutine->amcaninclude = false;
amroutine->amusemaintenanceworkmem = false;
+ amroutine->amhotblocking = true;
amroutine->amparallelvacuumoptions = VACUUM_OPTION_NO_PARALLEL;
amroutine->amkeytype = InvalidOid;
DROP TABLE brintest_3;
RESET enable_seqscan;
+-- test BRIN index doesn't block HOT update
+CREATE TABLE brin_hot (
+ id integer PRIMARY KEY,
+ val integer NOT NULL
+) WITH (autovacuum_enabled = off, fillfactor = 70);
+INSERT INTO brin_hot SELECT *, 0 FROM generate_series(1, 235);
+CREATE INDEX val_brin ON brin_hot using brin(val);
+CREATE FUNCTION wait_for_hot_stats() RETURNS void AS $$
+DECLARE
+ start_time timestamptz := clock_timestamp();
+ updated bool;
+BEGIN
+ -- we don't want to wait forever; loop will exit after 30 seconds
+ FOR i IN 1 .. 300 LOOP
+ SELECT (pg_stat_get_tuples_hot_updated('brin_hot'::regclass::oid) > 0) INTO updated;
+ EXIT WHEN updated;
+
+ -- wait a little
+ PERFORM pg_sleep_for('100 milliseconds');
+ -- reset stats snapshot so we can test again
+ PERFORM pg_stat_clear_snapshot();
+ END LOOP;
+ -- report time waited in postmaster log (where it won't change test output)
+ RAISE log 'wait_for_hot_stats delayed % seconds',
+ EXTRACT(epoch FROM clock_timestamp() - start_time);
+END
+$$ LANGUAGE plpgsql;
+UPDATE brin_hot SET val = -3 WHERE id = 42;
+-- We can't just call wait_for_hot_stats() at this point, because we only
+-- transmit stats when the session goes idle, and we probably didn't
+-- transmit the last couple of counts yet thanks to the rate-limiting logic
+-- in pgstat_report_stat(). But instead of waiting for the rate limiter's
+-- timeout to elapse, let's just start a new session. The old one will
+-- then send its stats before dying.
+\c -
+SELECT wait_for_hot_stats();
+ wait_for_hot_stats
+--------------------
+
+(1 row)
+
+SELECT pg_stat_get_tuples_hot_updated('brin_hot'::regclass::oid);
+ pg_stat_get_tuples_hot_updated
+--------------------------------
+ 1
+(1 row)
+
+DROP TABLE brin_hot;
+DROP FUNCTION wait_for_hot_stats();
+-- Test handling of index predicates - updating attributes in precicates
+-- should block HOT even for BRIN. We update a row that was not indexed
+-- due to the index predicate, and becomes indexable.
+CREATE TABLE brin_hot_2 (a int, b int);
+INSERT INTO brin_hot_2 VALUES (1, 100);
+CREATE INDEX ON brin_hot_2 USING brin (b) WHERE a = 2;
+UPDATE brin_hot_2 SET a = 2;
+EXPLAIN (COSTS OFF) SELECT * FROM brin_hot_2 WHERE a = 2 AND b = 100;
+ QUERY PLAN
+-----------------------------------
+ Seq Scan on brin_hot_2
+ Filter: ((a = 2) AND (b = 100))
+(2 rows)
+
+SELECT COUNT(*) FROM brin_hot_2 WHERE a = 2 AND b = 100;
+ count
+-------
+ 1
+(1 row)
+
+SET enable_seqscan = off;
+EXPLAIN (COSTS OFF) SELECT * FROM brin_hot_2 WHERE a = 2 AND b = 100;
+ QUERY PLAN
+---------------------------------------------
+ Bitmap Heap Scan on brin_hot_2
+ Recheck Cond: ((b = 100) AND (a = 2))
+ -> Bitmap Index Scan on brin_hot_2_b_idx
+ Index Cond: (b = 100)
+(4 rows)
+
+SELECT COUNT(*) FROM brin_hot_2 WHERE a = 2 AND b = 100;
+ count
+-------
+ 1
+(1 row)
+
DROP TABLE brintest_3;
RESET enable_seqscan;
+
+-- test BRIN index doesn't block HOT update
+CREATE TABLE brin_hot (
+ id integer PRIMARY KEY,
+ val integer NOT NULL
+) WITH (autovacuum_enabled = off, fillfactor = 70);
+
+INSERT INTO brin_hot SELECT *, 0 FROM generate_series(1, 235);
+CREATE INDEX val_brin ON brin_hot using brin(val);
+
+CREATE FUNCTION wait_for_hot_stats() RETURNS void AS $$
+DECLARE
+ start_time timestamptz := clock_timestamp();
+ updated bool;
+BEGIN
+ -- we don't want to wait forever; loop will exit after 30 seconds
+ FOR i IN 1 .. 300 LOOP
+ SELECT (pg_stat_get_tuples_hot_updated('brin_hot'::regclass::oid) > 0) INTO updated;
+ EXIT WHEN updated;
+
+ -- wait a little
+ PERFORM pg_sleep_for('100 milliseconds');
+ -- reset stats snapshot so we can test again
+ PERFORM pg_stat_clear_snapshot();
+ END LOOP;
+ -- report time waited in postmaster log (where it won't change test output)
+ RAISE log 'wait_for_hot_stats delayed % seconds',
+ EXTRACT(epoch FROM clock_timestamp() - start_time);
+END
+$$ LANGUAGE plpgsql;
+
+UPDATE brin_hot SET val = -3 WHERE id = 42;
+
+-- We can't just call wait_for_hot_stats() at this point, because we only
+-- transmit stats when the session goes idle, and we probably didn't
+-- transmit the last couple of counts yet thanks to the rate-limiting logic
+-- in pgstat_report_stat(). But instead of waiting for the rate limiter's
+-- timeout to elapse, let's just start a new session. The old one will
+-- then send its stats before dying.
+\c -
+
+SELECT wait_for_hot_stats();
+SELECT pg_stat_get_tuples_hot_updated('brin_hot'::regclass::oid);
+
+DROP TABLE brin_hot;
+DROP FUNCTION wait_for_hot_stats();
+
+-- Test handling of index predicates - updating attributes in precicates
+-- should block HOT even for BRIN. We update a row that was not indexed
+-- due to the index predicate, and becomes indexable.
+CREATE TABLE brin_hot_2 (a int, b int);
+INSERT INTO brin_hot_2 VALUES (1, 100);
+CREATE INDEX ON brin_hot_2 USING brin (b) WHERE a = 2;
+
+UPDATE brin_hot_2 SET a = 2;
+
+EXPLAIN (COSTS OFF) SELECT * FROM brin_hot_2 WHERE a = 2 AND b = 100;
+SELECT COUNT(*) FROM brin_hot_2 WHERE a = 2 AND b = 100;
+
+SET enable_seqscan = off;
+
+EXPLAIN (COSTS OFF) SELECT * FROM brin_hot_2 WHERE a = 2 AND b = 100;
+SELECT COUNT(*) FROM brin_hot_2 WHERE a = 2 AND b = 100;
projects / users / rhaas / postgres.git / commitdiff