Hi hackers,
I originally suggested $Š…UBJECT as part of the thread that ultimately led
to the addition of PROCESS_TOAST [0], but we decided not to proceed with
it. Recently, this idea came up again [1], so I thought I'd give it
another try.
The motivation for adding this option is to make it easier to VACUUM only a
relation's TOAST table. At the moment, you need to find the TOAST table by
examining a relation's reltoastrelid, and you need USAGE on the pg_toast
schema. This option could also help make it possible to call only
vac_update_datfrozenxid() without processing any relations, as discussed
elsewhere [2].
The demand for all these niche VACUUM options is likely limited, but it
does seem like there are some useful applications. If a new option is out
of the question, perhaps this functionality could be added to the existing
PROCESS_TOAST option.
[0] https://postgr.es/m/BA8951E9-1524-48C5-94AF-73B1F0D7857F%40amazon.com
[1] https://postgr.es/m/20221215191246.GA252861%40nathanxps13
[2] https://postgr.es/m/20221229213719.GA301584%40nathanxps13
--
Nathan Bossart
Amazon Web Services: https://aws.amazon.com
>From b123ddaf560a647536f5a7e52993401755da8650 Mon Sep 17 00:00:00 2001
From: Nathan Bossart <nathandboss...@gmail.com>
Date: Thu, 29 Dec 2022 15:31:49 -0800
Subject: [PATCH v1 1/1] add PROCESS_MAIN to VACUUM
---
doc/src/sgml/ref/vacuum.sgml | 13 +++++++++++++
doc/src/sgml/ref/vacuumdb.sgml | 15 +++++++++++++++
src/backend/commands/vacuum.c | 24 +++++++++++++++++++-----
src/backend/postmaster/autovacuum.c | 1 +
src/bin/psql/tab-complete.c | 4 ++--
src/bin/scripts/t/100_vacuumdb.pl | 7 +++++++
src/bin/scripts/vacuumdb.c | 24 ++++++++++++++++++++++++
src/include/commands/vacuum.h | 1 +
src/test/regress/expected/vacuum.out | 4 ++++
src/test/regress/sql/vacuum.sql | 5 +++++
10 files changed, 91 insertions(+), 7 deletions(-)
diff --git a/doc/src/sgml/ref/vacuum.sgml b/doc/src/sgml/ref/vacuum.sgml
index e14ead8826..bb634ae569 100644
--- a/doc/src/sgml/ref/vacuum.sgml
+++ b/doc/src/sgml/ref/vacuum.sgml
@@ -33,6 +33,7 @@ VACUUM [ FULL ] [ FREEZE ] [ VERBOSE ] [ ANALYZE ] [ <replaceable class="paramet
DISABLE_PAGE_SKIPPING [ <replaceable class="parameter">boolean</replaceable> ]
SKIP_LOCKED [ <replaceable class="parameter">boolean</replaceable> ]
INDEX_CLEANUP { AUTO | ON | OFF }
+ PROCESS_MAIN [ <replaceable class="parameter">boolean</replaceable> ]
PROCESS_TOAST [ <replaceable class="parameter">boolean</replaceable> ]
TRUNCATE [ <replaceable class="parameter">boolean</replaceable> ]
PARALLEL <replaceable class="parameter">integer</replaceable>
@@ -236,6 +237,18 @@ VACUUM [ FULL ] [ FREEZE ] [ VERBOSE ] [ ANALYZE ] [ <replaceable class="paramet
</listitem>
</varlistentry>
+ <varlistentry>
+ <term><literal>PROCESS_MAIN</literal></term>
+ <listitem>
+ <para>
+ Specifies that <command>VACUUM</command> should attempt to process the
+ main relation. This is usually the desired behavior and is the default.
+ Setting this option to false may be useful when it is only necessary to
+ vacuum a relation's corresponding <literal>TOAST</literal> table.
+ </para>
+ </listitem>
+ </varlistentry>
+
<varlistentry>
<term><literal>PROCESS_TOAST</literal></term>
<listitem>
diff --git a/doc/src/sgml/ref/vacuumdb.sgml b/doc/src/sgml/ref/vacuumdb.sgml
index 841aced3bd..74bac2d4ba 100644
--- a/doc/src/sgml/ref/vacuumdb.sgml
+++ b/doc/src/sgml/ref/vacuumdb.sgml
@@ -317,6 +317,21 @@ PostgreSQL documentation
</listitem>
</varlistentry>
+ <varlistentry>
+ <term><option>--no-process-main</option></term>
+ <listitem>
+ <para>
+ Skip the main relation.
+ </para>
+ <note>
+ <para>
+ This option is only available for servers running
+ <productname>PostgreSQL</productname> 16 and later.
+ </para>
+ </note>
+ </listitem>
+ </varlistentry>
+
<varlistentry>
<term><option>--no-process-toast</option></term>
<listitem>
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index ba965b8c7b..4dbad90039 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -113,6 +113,7 @@ ExecVacuum(ParseState *pstate, VacuumStmt *vacstmt, bool isTopLevel)
bool freeze = false;
bool full = false;
bool disable_page_skipping = false;
+ bool process_main = true;
bool process_toast = true;
ListCell *lc;
@@ -164,6 +165,8 @@ ExecVacuum(ParseState *pstate, VacuumStmt *vacstmt, bool isTopLevel)
params.index_cleanup = get_vacoptval_from_boolean(opt);
}
}
+ else if (strcmp(opt->defname, "process_main") == 0)
+ process_main = defGetBoolean(opt);
else if (strcmp(opt->defname, "process_toast") == 0)
process_toast = defGetBoolean(opt);
else if (strcmp(opt->defname, "truncate") == 0)
@@ -216,7 +219,8 @@ ExecVacuum(ParseState *pstate, VacuumStmt *vacstmt, bool isTopLevel)
(freeze ? VACOPT_FREEZE : 0) |
(full ? VACOPT_FULL : 0) |
(disable_page_skipping ? VACOPT_DISABLE_PAGE_SKIPPING : 0) |
- (process_toast ? VACOPT_PROCESS_TOAST : 0);
+ (process_toast ? VACOPT_PROCESS_TOAST : 0) |
+ (process_main ? VACOPT_PROCESS_MAIN : 0);
/* sanity checks on options */
Assert(params.options & (VACOPT_VACUUM | VACOPT_ANALYZE));
@@ -1994,10 +1998,12 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params)
/*
* Remember the relation's TOAST relation for later, if the caller asked
* us to process it. In VACUUM FULL, though, the toast table is
- * automatically rebuilt by cluster_rel so we shouldn't recurse to it.
+ * automatically rebuilt by cluster_rel so we shouldn't recurse to it
+ * unless PROCESS_MAIN is disabled.
*/
if ((params->options & VACOPT_PROCESS_TOAST) != 0 &&
- (params->options & VACOPT_FULL) == 0)
+ ((params->options & VACOPT_FULL) == 0 ||
+ (params->options & VACOPT_PROCESS_MAIN) == 0))
toast_relid = rel->rd_rel->reltoastrelid;
else
toast_relid = InvalidOid;
@@ -2016,7 +2022,8 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params)
/*
* Do the actual work --- either FULL or "lazy" vacuum
*/
- if (params->options & VACOPT_FULL)
+ if (params->options & VACOPT_FULL &&
+ params->options & VACOPT_PROCESS_MAIN)
{
ClusterParams cluster_params = {0};
@@ -2030,7 +2037,7 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params)
/* VACUUM FULL is now a variant of CLUSTER; see cluster.c */
cluster_rel(relid, InvalidOid, &cluster_params);
}
- else
+ else if (params->options & VACOPT_PROCESS_MAIN)
table_relation_vacuum(rel, params, vac_strategy);
/* Roll back any GUC changes executed by index functions */
@@ -2057,7 +2064,14 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params)
* totally unimportant for toast relations.
*/
if (toast_relid != InvalidOid)
+ {
+ /* we force VACOPT_PROCESS_MAIN so vacuum_rel() processes it */
+ bool force_opt = ((params->options & VACOPT_PROCESS_MAIN) == 0);
+
+ params->options |= force_opt ? VACOPT_PROCESS_MAIN : 0;
vacuum_rel(toast_relid, NULL, params);
+ params->options &= force_opt ? ~VACOPT_PROCESS_MAIN : ~0;
+ }
/*
* Now release the session-level lock on the main table.
diff --git a/src/backend/postmaster/autovacuum.c b/src/backend/postmaster/autovacuum.c
index 0746d80224..65c6fb6a27 100644
--- a/src/backend/postmaster/autovacuum.c
+++ b/src/backend/postmaster/autovacuum.c
@@ -2856,6 +2856,7 @@ table_recheck_autovac(Oid relid, HTAB *table_toast_map,
/* Note that this skips toast relations */
tab->at_params.options = (dovacuum ? VACOPT_VACUUM : 0) |
+ (dovacuum ? VACOPT_PROCESS_MAIN : 0) |
(doanalyze ? VACOPT_ANALYZE : 0) |
(!wraparound ? VACOPT_SKIP_LOCKED : 0);
diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c
index 2a3921937c..ce4c16c8a3 100644
--- a/src/bin/psql/tab-complete.c
+++ b/src/bin/psql/tab-complete.c
@@ -4551,9 +4551,9 @@ psql_completion(const char *text, int start, int end)
if (ends_with(prev_wd, '(') || ends_with(prev_wd, ','))
COMPLETE_WITH("FULL", "FREEZE", "ANALYZE", "VERBOSE",
"DISABLE_PAGE_SKIPPING", "SKIP_LOCKED",
- "INDEX_CLEANUP", "PROCESS_TOAST",
+ "INDEX_CLEANUP", "PROCESS_MAIN", "PROCESS_TOAST",
"TRUNCATE", "PARALLEL");
- else if (TailMatches("FULL|FREEZE|ANALYZE|VERBOSE|DISABLE_PAGE_SKIPPING|SKIP_LOCKED|PROCESS_TOAST|TRUNCATE"))
+ else if (TailMatches("FULL|FREEZE|ANALYZE|VERBOSE|DISABLE_PAGE_SKIPPING|SKIP_LOCKED|PROCESS_MAIN|PROCESS_TOAST|TRUNCATE"))
COMPLETE_WITH("ON", "OFF");
else if (TailMatches("INDEX_CLEANUP"))
COMPLETE_WITH("AUTO", "ON", "OFF");
diff --git a/src/bin/scripts/t/100_vacuumdb.pl b/src/bin/scripts/t/100_vacuumdb.pl
index e5343774fe..fd7cb944cb 100644
--- a/src/bin/scripts/t/100_vacuumdb.pl
+++ b/src/bin/scripts/t/100_vacuumdb.pl
@@ -65,6 +65,13 @@ $node->issues_sql_like(
$node->command_fails(
[ 'vacuumdb', '--analyze-only', '--no-truncate', 'postgres' ],
'--analyze-only and --no-truncate specified together');
+$node->issues_sql_like(
+ [ 'vacuumdb', '--no-process-main', 'postgres' ],
+ qr/statement: VACUUM \(PROCESS_MAIN FALSE\).*;/,
+ 'vacuumdb --no-process-main');
+$node->command_fails(
+ [ 'vacuumdb', '--analyze-only', '--no-process-main', 'postgres' ],
+ '--analyze-only and --no-process_main specified together');
$node->issues_sql_like(
[ 'vacuumdb', '--no-process-toast', 'postgres' ],
qr/statement: VACUUM \(PROCESS_TOAST FALSE\).*;/,
diff --git a/src/bin/scripts/vacuumdb.c b/src/bin/scripts/vacuumdb.c
index 272e37d290..7424e75668 100644
--- a/src/bin/scripts/vacuumdb.c
+++ b/src/bin/scripts/vacuumdb.c
@@ -43,6 +43,7 @@ typedef struct vacuumingOptions
bool no_index_cleanup;
bool force_index_cleanup;
bool do_truncate;
+ bool process_main;
bool process_toast;
} vacuumingOptions;
@@ -120,6 +121,7 @@ main(int argc, char *argv[])
{"force-index-cleanup", no_argument, NULL, 9},
{"no-truncate", no_argument, NULL, 10},
{"no-process-toast", no_argument, NULL, 11},
+ {"no-process-main", no_argument, NULL, 12},
{NULL, 0, NULL, 0}
};
@@ -147,6 +149,7 @@ main(int argc, char *argv[])
vacopts.no_index_cleanup = false;
vacopts.force_index_cleanup = false;
vacopts.do_truncate = true;
+ vacopts.process_main = true;
vacopts.process_toast = true;
pg_logging_init(argv[0]);
@@ -259,6 +262,9 @@ main(int argc, char *argv[])
case 11:
vacopts.process_toast = false;
break;
+ case 12:
+ vacopts.process_main = false;
+ break;
default:
/* getopt_long already emitted a complaint */
pg_log_error_hint("Try \"%s --help\" for more information.", progname);
@@ -311,6 +317,9 @@ main(int argc, char *argv[])
if (!vacopts.do_truncate)
pg_fatal("cannot use the \"%s\" option when performing only analyze",
"no-truncate");
+ if (!vacopts.process_main)
+ pg_fatal("cannot use the \"%s\" option when performing only analyze",
+ "no-process-main");
if (!vacopts.process_toast)
pg_fatal("cannot use the \"%s\" option when performing only analyze",
"no-process-toast");
@@ -507,6 +516,13 @@ vacuum_one_database(ConnParams *cparams,
"no-truncate", "12");
}
+ if (!vacopts->process_main && PQserverVersion(conn) < 160000)
+ {
+ PQfinish(conn);
+ pg_fatal("cannot use the \"%s\" option on server versions older than PostgreSQL %s",
+ "no-process-main", "16");
+ }
+
if (!vacopts->process_toast && PQserverVersion(conn) < 140000)
{
PQfinish(conn);
@@ -950,6 +966,13 @@ prepare_vacuum_command(PQExpBuffer sql, int serverVersion,
appendPQExpBuffer(sql, "%sTRUNCATE FALSE", sep);
sep = comma;
}
+ if (!vacopts->process_main)
+ {
+ /* PROCESS_MAIN is supported since v16 */
+ Assert(serverVersion >= 160000);
+ appendPQExpBuffer(sql, "%sPROCESS_MAIN FALSE", sep);
+ sep = comma;
+ }
if (!vacopts->process_toast)
{
/* PROCESS_TOAST is supported since v14 */
@@ -1057,6 +1080,7 @@ help(const char *progname)
printf(_(" --min-mxid-age=MXID_AGE minimum multixact ID age of tables to vacuum\n"));
printf(_(" --min-xid-age=XID_AGE minimum transaction ID age of tables to vacuum\n"));
printf(_(" --no-index-cleanup don't remove index entries that point to dead tuples\n"));
+ printf(_(" --no-process-main skip the main relation\n"));
printf(_(" --no-process-toast skip the TOAST table associated with the table to vacuum\n"));
printf(_(" --no-truncate don't truncate empty pages at the end of the table\n"));
printf(_(" -n, --schema=PATTERN vacuum tables in the specified schema(s) only\n"));
diff --git a/src/include/commands/vacuum.h b/src/include/commands/vacuum.h
index 2f274f2bec..80fca14619 100644
--- a/src/include/commands/vacuum.h
+++ b/src/include/commands/vacuum.h
@@ -188,6 +188,7 @@ typedef struct VacAttrStats
#define VACOPT_SKIP_LOCKED 0x20 /* skip if cannot get lock */
#define VACOPT_PROCESS_TOAST 0x40 /* process the TOAST table, if any */
#define VACOPT_DISABLE_PAGE_SKIPPING 0x80 /* don't skip any pages */
+#define VACOPT_PROCESS_MAIN 0x100 /* process main relation */
/*
* Values used by index_cleanup and truncate params.
diff --git a/src/test/regress/expected/vacuum.out b/src/test/regress/expected/vacuum.out
index 0035d158b7..d3880f67b5 100644
--- a/src/test/regress/expected/vacuum.out
+++ b/src/test/regress/expected/vacuum.out
@@ -282,6 +282,10 @@ ALTER TABLE vactst ALTER COLUMN t SET STORAGE EXTERNAL;
VACUUM (PROCESS_TOAST FALSE) vactst;
VACUUM (PROCESS_TOAST FALSE, FULL) vactst;
ERROR: PROCESS_TOAST required with VACUUM FULL
+-- PROCESS_MAIN option
+VACUUM (PROCESS_MAIN FALSE) vactst;
+VACUUM (PROCESS_MAIN FALSE, PROCESS_TOAST FALSE) vactst;
+VACUUM (PROCESS_MAIN FALSE, FULL) vactst;
DROP TABLE vaccluster;
DROP TABLE vactst;
DROP TABLE vacparted;
diff --git a/src/test/regress/sql/vacuum.sql b/src/test/regress/sql/vacuum.sql
index 9faa8a34a6..d2893e0c37 100644
--- a/src/test/regress/sql/vacuum.sql
+++ b/src/test/regress/sql/vacuum.sql
@@ -237,6 +237,11 @@ ALTER TABLE vactst ALTER COLUMN t SET STORAGE EXTERNAL;
VACUUM (PROCESS_TOAST FALSE) vactst;
VACUUM (PROCESS_TOAST FALSE, FULL) vactst;
+-- PROCESS_MAIN option
+VACUUM (PROCESS_MAIN FALSE) vactst;
+VACUUM (PROCESS_MAIN FALSE, PROCESS_TOAST FALSE) vactst;
+VACUUM (PROCESS_MAIN FALSE, FULL) vactst;
+
DROP TABLE vaccluster;
DROP TABLE vactst;
DROP TABLE vacparted;
--
2.25.1
