diff --git a/doc/src/sgml/ref/vacuum.sgml b/doc/src/sgml/ref/vacuum.sgml
index 19fd748dde0b523be578405479a2c23384f6b1f3..dee1c5bad31cb76aff5859a1c2d55e592f32a4de 100644
--- a/doc/src/sgml/ref/vacuum.sgml
+++ b/doc/src/sgml/ref/vacuum.sgml
@@ -21,7 +21,7 @@ PostgreSQL documentation
<refsynopsisdiv>
<synopsis>
-VACUUM [ ( { FULL | FREEZE | VERBOSE | ANALYZE } [, ...] ) ] [ <replaceable class="PARAMETER">table_name</replaceable> [ (<replaceable class="PARAMETER">column_name</replaceable> [, ...] ) ] ]
+VACUUM [ ( { FULL | FREEZE | VERBOSE | ANALYZE | DISABLE_PAGE_SKIPPING } [, ...] ) ] [ <replaceable class="PARAMETER">table_name</replaceable> [ (<replaceable class="PARAMETER">column_name</replaceable> [, ...] ) ] ]
VACUUM [ FULL ] [ FREEZE ] [ VERBOSE ] [ <replaceable class="PARAMETER">table_name</replaceable> ]
VACUUM [ FULL ] [ FREEZE ] [ VERBOSE ] ANALYZE [ <replaceable class="PARAMETER">table_name</replaceable> [ (<replaceable class="PARAMETER">column_name</replaceable> [, ...] ) ] ]
</synopsis>
@@ -129,6 +129,25 @@ VACUUM [ FULL ] [ FREEZE ] [ VERBOSE ] ANALYZE [ <replaceable class="PARAMETER">
</listitem>
</varlistentry>
+ <varlistentry>
+ <term><literal>DISABLE_PAGE_SKIPPING</literal></term>
+ <listitem>
+ <para>
+ Normally, <command>VACUUM</> will skip pages based on the <link
+ linkend="vacuum-for-visibility-map">visibility map</>. Pages where
+ all tuples are known to be frozen can always be skipped, and those
+ where all tuples are known to be visible to all transactions may be
+ skipped except when performing an aggressive vacuum. Furthermore,
+ except when performing an aggressive vacuum, some pages may be skipped
+ in order to avoid waiting for other sessions to finish using them.
+ This option disables all page-skipping behavior, and is intended to
+ be used only the contents of the visibility map are thought to
+ be suspect, which should happen only if there is a hardware or software
+ issue causing database corruption.
+ </para>
+ </listitem>
+ </varlistentry>
+
<varlistentry>
<term><replaceable class="PARAMETER">table_name</replaceable></term>
<listitem>
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 25a55ab0a5a8a4662a9a8809cf429782871e8094..0563e6347430d43c6cd5d4be5c8456fcc3406946 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -185,6 +185,15 @@ vacuum(int options, RangeVar *relation, Oid relid, VacuumParams *params,
errmsg("%s cannot be executed from VACUUM or ANALYZE",
stmttype)));
+ /*
+ * Sanity check DISABLE_PAGE_SKIPPING option.
+ */
+ if ((options & VACOPT_FULL) != 0 &&
+ (options & VACOPT_DISABLE_PAGE_SKIPPING) != 0)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("VACUUM option DISABLE_PAGE_SKIPPING cannot be used with FULL")));
+
/*
* Send info about dead objects to the statistics collector, unless we are
* in autovacuum --- autovacuum.c does this for itself.
diff --git a/src/backend/commands/vacuumlazy.c b/src/backend/commands/vacuumlazy.c
index cb5777ffdf9310d626521599c5fa519edd299d2c..32b6fddc6220c63a6287f1e789241e28aaf6cf11 100644
--- a/src/backend/commands/vacuumlazy.c
+++ b/src/backend/commands/vacuumlazy.c
@@ -137,8 +137,9 @@ static BufferAccessStrategy vac_strategy;
/* non-export function prototypes */
-static void lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
- Relation *Irel, int nindexes, bool aggressive);
+static void lazy_scan_heap(Relation onerel, int options,
+ LVRelStats *vacrelstats, Relation *Irel, int nindexes,
+ bool aggressive);
static void lazy_vacuum_heap(Relation onerel, LVRelStats *vacrelstats);
static bool lazy_check_needs_freeze(Buffer buf, bool *hastup);
static void lazy_vacuum_index(Relation indrel,
@@ -223,15 +224,17 @@ lazy_vacuum_rel(Relation onerel, int options, VacuumParams *params,
&MultiXactCutoff, &mxactFullScanLimit);
/*
- * We request an aggressive scan if either the table's frozen Xid is now
- * older than or equal to the requested Xid full-table scan limit; or if
- * the table's minimum MultiXactId is older than or equal to the requested
- * mxid full-table scan limit.
+ * We request an aggressive scan if the table's frozen Xid is now older
+ * than or equal to the requested Xid full-table scan limit; or if the
+ * table's minimum MultiXactId is older than or equal to the requested
+ * mxid full-table scan limit; or if DISABLE_PAGE_SKIPPING was specified.
*/
aggressive = TransactionIdPrecedesOrEquals(onerel->rd_rel->relfrozenxid,
xidFullScanLimit);
aggressive |= MultiXactIdPrecedesOrEquals(onerel->rd_rel->relminmxid,
mxactFullScanLimit);
+ if (options & VACOPT_DISABLE_PAGE_SKIPPING)
+ aggressive = true;
vacrelstats = (LVRelStats *) palloc0(sizeof(LVRelStats));
@@ -246,7 +249,7 @@ lazy_vacuum_rel(Relation onerel, int options, VacuumParams *params,
vacrelstats->hasindex = (nindexes > 0);
/* Do the vacuuming */
- lazy_scan_heap(onerel, vacrelstats, Irel, nindexes, aggressive);
+ lazy_scan_heap(onerel, options, vacrelstats, Irel, nindexes, aggressive);
/* Done with indexes */
vac_close_indexes(nindexes, Irel, NoLock);
@@ -441,7 +444,7 @@ vacuum_log_cleanup_info(Relation rel, LVRelStats *vacrelstats)
* reference them have been killed.
*/
static void
-lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
+lazy_scan_heap(Relation onerel, int options, LVRelStats *vacrelstats,
Relation *Irel, int nindexes, bool aggressive)
{
BlockNumber nblocks,
@@ -542,25 +545,28 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
* the last page. This is worth avoiding mainly because such a lock must
* be replayed on any hot standby, where it can be disruptive.
*/
- for (next_unskippable_block = 0;
- next_unskippable_block < nblocks;
- next_unskippable_block++)
+ next_unskippable_block = 0;
+ if ((options & VACOPT_DISABLE_PAGE_SKIPPING) == 0)
{
- uint8 vmstatus;
-
- vmstatus = visibilitymap_get_status(onerel, next_unskippable_block,
- &vmbuffer);
- if (aggressive)
+ while (next_unskippable_block < nblocks)
{
- if ((vmstatus & VISIBILITYMAP_ALL_FROZEN) == 0)
- break;
- }
- else
- {
- if ((vmstatus & VISIBILITYMAP_ALL_VISIBLE) == 0)
- break;
+ uint8 vmstatus;
+
+ vmstatus = visibilitymap_get_status(onerel, next_unskippable_block,
+ &vmbuffer);
+ if (aggressive)
+ {
+ if ((vmstatus & VISIBILITYMAP_ALL_FROZEN) == 0)
+ break;
+ }
+ else
+ {
+ if ((vmstatus & VISIBILITYMAP_ALL_VISIBLE) == 0)
+ break;
+ }
+ vacuum_delay_point();
+ next_unskippable_block++;
}
- vacuum_delay_point();
}
if (next_unskippable_block >= SKIP_PAGES_THRESHOLD)
@@ -594,26 +600,29 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
if (blkno == next_unskippable_block)
{
/* Time to advance next_unskippable_block */
- for (next_unskippable_block++;
- next_unskippable_block < nblocks;
- next_unskippable_block++)
+ next_unskippable_block++;
+ if ((options & VACOPT_DISABLE_PAGE_SKIPPING) == 0)
{
- uint8 vmskipflags;
-
- vmskipflags = visibilitymap_get_status(onerel,
- next_unskippable_block,
- &vmbuffer);
- if (aggressive)
+ while (next_unskippable_block < nblocks)
{
- if ((vmskipflags & VISIBILITYMAP_ALL_FROZEN) == 0)
- break;
- }
- else
- {
- if ((vmskipflags & VISIBILITYMAP_ALL_VISIBLE) == 0)
- break;
+ uint8 vmskipflags;
+
+ vmskipflags = visibilitymap_get_status(onerel,
+ next_unskippable_block,
+ &vmbuffer);
+ if (aggressive)
+ {
+ if ((vmskipflags & VISIBILITYMAP_ALL_FROZEN) == 0)
+ break;
+ }
+ else
+ {
+ if ((vmskipflags & VISIBILITYMAP_ALL_VISIBLE) == 0)
+ break;
+ }
+ vacuum_delay_point();
+ next_unskippable_block++;
}
- vacuum_delay_point();
}
/*
@@ -1054,7 +1063,7 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
}
else
{
- bool tuple_totally_frozen;
+ bool tuple_totally_frozen;
num_tuples += 1;
hastup = true;
@@ -1064,8 +1073,8 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
* freezing. Note we already have exclusive buffer lock.
*/
if (heap_prepare_freeze_tuple(tuple.t_data, FreezeLimit,
- MultiXactCutoff, &frozen[nfrozen],
- &tuple_totally_frozen))
+ MultiXactCutoff, &frozen[nfrozen],
+ &tuple_totally_frozen))
frozen[nfrozen++].offset = offnum;
if (!tuple_totally_frozen)
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 2c950f937c49a1513867c590592ba412726c023f..edf4516dacd55c0f4859eae6a00ecbb23c2c2d31 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -9370,6 +9370,16 @@ vacuum_option_elem:
| VERBOSE { $$ = VACOPT_VERBOSE; }
| FREEZE { $$ = VACOPT_FREEZE; }
| FULL { $$ = VACOPT_FULL; }
+ | IDENT
+ {
+ if (strcmp($1, "disable_page_skipping") == 0)
+ $$ = VACOPT_DISABLE_PAGE_SKIPPING;
+ else
+ ereport(ERROR,
+ (errcode(ERRCODE_SYNTAX_ERROR),
+ errmsg("unrecognized VACUUM option \"%s\"", $1),
+ parser_errposition(@1)));
+ }
;
AnalyzeStmt:
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index 714cf1550fd1e158cd88786c2e8576dccd18eeb4..d36d9c6d01967ae66741367422fc641784086bcd 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -2822,7 +2822,8 @@ typedef enum VacuumOption
VACOPT_FREEZE = 1 << 3, /* FREEZE option */
VACOPT_FULL = 1 << 4, /* FULL (non-concurrent) vacuum */
VACOPT_NOWAIT = 1 << 5, /* don't wait to get lock (autovacuum only) */
- VACOPT_SKIPTOAST = 1 << 6 /* don't process the TOAST table, if any */
+ VACOPT_SKIPTOAST = 1 << 6, /* don't process the TOAST table, if any */
+ VACOPT_DISABLE_PAGE_SKIPPING = 1 << 7 /* don't skip any pages */
} VacuumOption;
typedef struct VacuumStmt
diff --git a/src/test/regress/expected/vacuum.out b/src/test/regress/expected/vacuum.out
index d2d750382864581da834bdc2871639bfb6227fe6..9b604be4b62e1b472bdc60a31b5c3b19b67f227c 100644
--- a/src/test/regress/expected/vacuum.out
+++ b/src/test/regress/expected/vacuum.out
@@ -79,5 +79,6 @@ ERROR: ANALYZE cannot be executed from VACUUM or ANALYZE
CONTEXT: SQL function "do_analyze" statement 1
SQL function "wrap_do_analyze" statement 1
VACUUM FULL vactst;
+VACUUM (DISABLE_PAGE_SKIPPING) vaccluster;
DROP TABLE vaccluster;
DROP TABLE vactst;
diff --git a/src/test/regress/sql/vacuum.sql b/src/test/regress/sql/vacuum.sql
index f8412016cf3fc23bad621f5760e3126ea312e0a0..7b819f654ddf51f0a53fb39de0726bc6bbc50d9f 100644
--- a/src/test/regress/sql/vacuum.sql
+++ b/src/test/regress/sql/vacuum.sql
@@ -60,5 +60,7 @@ VACUUM FULL pg_database;
VACUUM FULL vaccluster;
VACUUM FULL vactst;
+VACUUM (DISABLE_PAGE_SKIPPING) vaccluster;
+
DROP TABLE vaccluster;
DROP TABLE vactst;